articles, collections

Here I am gonna posts geometry  articles, notes  and problem collections,  that I create or collect from sites around the internet (except the Tournament Of Towns Conferences). All the aother articles, are also in the other pages. Free books, old and recent, are collected here.

Paris Pamfilos - Geometricon
190 pages' Sample of Geometricon, a 800 pages Geometry book in English, currently available only in Greek                        (his homepage , source of this file)

Problems collections by others, from the internet

• Abdilkadir Altıntaş & Ercole Suppa - Sangaku problems
• Amir Hossein Parvardi - (25) Geometry Problems (January 6, 2011) <solved in links>
• Amir Hossein Parvardi - 150 Nice Geometry Problems (January 9, 2011) <solved in links>
• Amir Hossein Parvardi - 60 Geometry Problems (October 13, 2011) <solved in links>
• David Altisio - 100 Geometry problems (August 30 2014) 
• David Altisio - 100 Geometry problems, Solutions edited by Alvin Zou (April 26 2015)  (source)
• Ercole Suppa - Geometry Marathon (Mathlinks Forum, July 14, 2012) <521 solved in links>
• Liverpool26 - 111 Nice Geometry Problems from Mathscope (January 01,2013) (source)
• Tran Quang Hung - Red Geometry <118 unsolved>

Notable geometry articles

• Alexander Skutin - Some new theorems in plane geometry
• Alexander Skutin - Creative Geometry
• Alexander Skutin - Cosmology of Plane Geometry 2021 version (contains problems by Tran Quang Hung, Kadir Altintas and Antreas Hatzipolakis) (intro)
• Milton Donaire Peña - Area Poligonal 2020 (no7)
• Milton Donaire Peña - Region-Cuadrangular (no6).

Non English problem collections

• Geometri Günlüğü 001-500 (Turkish) by Abdilkadir Altıntaş
• Geometri Günlüğü 501-849 (Turkish) by Abdilkadir Altıntaş

Tran Viet Hung (collected here)

• 001-200 Mixtilinear problems (Vietnamese)
• 201-400 Mixtilinear problems  (Vietnamese)
• 401-600 Mixtilinear problems  (Vietnamese / English >= 436)
• 601-800 Mixtilinear problems  (English)
• 801-1000 Mixtilinear problems  (English)
• 001-200 PhuTruong problems  (Vietnamese / English >= 120)
• 201-400 PhuTruong problems  (English)
• 401-600 PhuTruong problems  (English)

Concurrent lines, problems without words
Hans Walser - Schnittpunkte :
101-200 ,  201-300 ,  301-400 ,   401-500 ,  501-600,  601-700 ,  701-800 

source: www.walser-h-m.ch/hans/ 

problem collections that do not contain only geometry

• Original Problems Proposed by Stanley Rabinowitz 1963–2005 (Math-Pro Press 2006)
• Mathscope, All the best from Vietnamese Problem Solving Journals (f40)  (a collection of problems selected from Vietnamese math journals (particularly Mathematics and the Youth from the last 10 years), compiled by Phạm Vǎn Thuận. At this moment it contains 424 problems. Updated: February 12, 2007)
• Collection of Inequalities (f41) (a collection of inequalities published in various math journals (a majority in Crux Mathematicorum) and books, compiled by Eckard Specht. At this moment it contains 1454±ε problems. Updated: October 22, 2006)

sources:
analgeomatica.wordpress.com  (Tran Quang Hung)
artofproblemsolving.com  (Amir Hossein Parvardi, David Altisio, Ercole Suppa)
mathscope.org  (liverpool26)
www.imomath.com (mathscope, collection of inequalities)
The School Yard Olympiad facebook group (Geometri Günlüğü)


My problem collections in English

• 397 geometry problems from  Sobregeometrias SX SG
• 345 geometry problems from 8floxes.com  
• 259 geometry writings by Christopher J. Bradley
• 127 geometry problems from fb group JUVENTUD GEÓMETRA (2nd edition)
• 50 geometry problems from fb group JUVENTUD MATEMÁTICA

sources:

8foxes.blogspot.com (blogspot, inactive)

JUVENTUD GEÓMETRA (fb group, incactive)

JUVENTUD MATEMÁTICA (fb group, incactive)

Geito Mr.G - SobreGeometrias (blogspot, incactive)

sites.google.com/a/8foxes.com/www/ (blogspot, inactive)

Sobre Geometrias SG SX (wordpress, incactive)

Sobre Geometrias SG (fb page, incactive)

Sobre Geometrias SG SX (fb group, incactive)

people.bath.ac.uk/masgcs/bradley.html (Bradley)

Of Historic Value

• Elisha Scott Loomis -  The Pythagorean Proposition (2nd ed.1940, 285 pages) <370 proofs>  

• McDonald Kirk - A solution to the problem of Apollonius (19 May 1964)

Geometric Transformations

• Evan Chen - Euclidean Geometry in Mathematical Olympiads, Chapter 8 - Inversion
• Kenji Kozai & Shlomo Libeskind - Circle Inversions and Applications to Euclidean Geometry (January 9, 2009)
• Tom Davis - Inversion in a Circle (March 23, 2011)
• Zvezdelina Stankova - Inversion in the plane (September 26 2004)  
• Unknown - An Introduction to Projective Geometry, 06-10-21_Geom2006_2 (based on Yaglom's Geometric Transformations)

Articles - Notes 

• Dominik Teiml - The Euler Line, proofs, properties, and applications (May 2013)
• J. Marshall Unger - A collection of 30 Sangaku problems (12 Jan16)
• Heather Macbeth - Collinearity and Concurrence (22 March 2009) (Deputy Team Leader for New Zealand)
• Po-Shen Loh - Collinearity And Concurrence  (23 June 2008) (Deputy Team Leader for the United States)
• Quines Joshua Carl - Pascal's Τheorem  (5 Jan 2017)
• Nicula Virgil , Pohoata Cosmin - A Stronger Form of the Steiner-Lehmus Theorem (Journal for Geometry and Graphics , Volume 13 (2009), No. 1, 25–27)
• Pohoata Cosmin - Harmonic quadrilaterals revisited (Gazeta Marematica, Seria A, Nr. 1 -2.2011)
• Rapanos Nikolaos - The complete quadrilateral and its properties (July 7, 2009)
• Rapanos Nikolaos - The harmonic quadrilateral and its properties (July 7, 2009)
• Richter- Gebert J. - Pappus’s Theorem: Nine Proofs  and Three Variations (2011)
• Suppa Ercole - Divisione Armonica (17-20 October 2010) (Italian)
• Victoria Krakovna - Concurrency and Collinearity (2010) (Deputy Leader for Canada)
• Vipul Naik - Co-Incidense Problems And Methods (India IMO Training Camp)
• Zarathustra Brady - Some cross ratios (written for high school students) 

Barycentric Coordinates

from International Journal of Computer Discovered Mathematics (www.journal-1.eu)

• Francisco Javier García Capitán -Barycentric Coordinates   (Vol.0 2015 pp.32-48)
• Francisco Javier García Capitán - Posing and Solving Problems with Barycentric Coordinates,  (Vol.1. No.1. 2016 pp.36-44)
• S. Grozdev and D. Dekov - Barycentric Coordinates: Formula Sheet, (Vol.1. No.2. 2016 pp.75-82)

Geometry articles from: (collected here)
The International Journal of Advances in Applied Mathematics and Mechanics (IJAAMM) (www.ijaamm.com)

1. Dasari Naga Vijay Krishna - A short note on Floor van Lamoen’s Cyclic Hexagon (v4n3p4_22-31)  
2. Dasari Naga Vijay Krishna - A note on special cases of Van Aubel’s theorem (v5n4p4_30-51)
3. Dasari Naga Vijay Krishna​ - ​​On a Conic Through Twelve Notable Points (v7n2p1_1-15)

Geometry articles from: (collected here)
Romanian Mathematical Magazine (RMM) (www.ssmrmh.ro)

1. Daniel Sitaru - 6 areas of 6 famous pedal triangles (Romania)
2. Daniel Sitaru - Napoleon outer triangle revisited (Romania)
3. Daniel Sitaru,Claudia Nănuți - The heptagonal triangle revisited (Romania)
4. Jose Ferreira de Queiroz Filho - Gergonne point of a triangle and it's distance from any point in the plane (Brazil)
5. Jose Ferreira de Queiroz Filho - Bevan's point in a brazilian approach (Brazil)
6. Nguyen Ngoc Giang - The creation of the Steiner-Lehmus’ theorem (Ho Chi Minh City - Vietnam)
7. Thanasis Gakopoulos - Gakopoulos' Lemmas (Greece)
8. Thanasis Gakopoulos - Gakopoulos' Lemma II (Greece)
9. Thanasis Gakopoulos,Dimitris Blatsis  - Plagiogonal Plane Coordinate System, / area of polygon (n-sided) (Greece)
10. Thanasis Gakopoulos - Metric Relations for mixtlinear incircles and excircles (Greece)
11. Thanasis Gakopoulos -Gakopoulos' special transversals (Greece)

Geometry Articles by Crux (collected here)

Index of Geometry Articles of  #  22 -38 (pdf links)

• A Duality for Bicentric Quadrilaterals by Michel Bataille  35.5 
• A Maximum Vertical Angle I  by G.D. Chakerian and M.S. Klamkin 30.4 
• A Maximum Vertical Angle II  by D. Ruoff and J.C. Fisher 30.4. 
• A Nest of Euler Inequalities by Luo Qi 37.5 
• A Nice COMC Problem (B12 1999) by Daryl Tingley 26.7 [COMC = Canadian Open Mathematics Challenge]
• A Revival of an Old Construction Problem by Barukh Ziv 28.8 
• A Solution to Gibson's and Rodgers' Problem in 3 Dimensions by Nguyen Minh Ha 36.8 
• A Spatial Problem Solved with Stereographic Projection by Shay Gueron & Oran Lang 26.8 
• A Typical Problem on an Entrance Exam for the École Polytechnique by Ross Honsberger 38.3 
• A Vector Introduction to the Orthopole by Michel Bataille 31.5 
• About the Japanese Theorem by Nicuşor Minculete, Cătălin Barbu & Gheorghe Szöllősy 38.5 
• An Efficient Construction of the Golden Section by Kurt Hofstetter 32.6 
• An Industrial Application of Spherical Inversion by Edward Crane 28.6 
• Another Look at the Volume of a Tetrahedron by Nairi M. Sedrakyan 27.4
• Another Unlikely Concurrence by Jean-Louis Ayme 29.8
• Brahmagupta Quadrilaterals,  A Description by K. R. S. Sastry29.1
• Butterfly Metamorphosis by  Andy Liu 33.3
• Ceva meets Pythagoras! by K.R.S Sastry 22.5
• Chasing Imaginary Triangles  by Ian VanderBurgh & Serge D'Alessio 31.7
• Cyclic ratio sums and products by Branko Grünbaum 24.1
• Dissecting Squares into Similar Rectangles by Andy Liu 22.6
• Dissecting Triangle into Isosceles Triangles by Byung-Kyu Chun, Andy Liu & Daniel van Vliet 22.3
• Eight Proofs of One Theorem by Jooyong Ahn, Hojoo Lee & Choongyup Sung 27.6
• Euler's Triangle Theorem by G.C. Shephard 25.3
• Folding the Regular Heptagon by Robert Geretschläger 23.2
• Folding the Regular Nonagon by Robert Geretschläger 23.4
• Generalisations of a Four-Square Theorem by Hiroshi Okumura & John F. Rigby 25.1
• Geometric Constructions of Mixtilinear Incircles by Cosmin Pohoata 35.2
• Heronian Triangles with Associated Inradii in Arithmetic Progression by Paul Yiu 23.3
• Hexagons and Inequalities by Yakub N. Aliyev 32.7
• Inequalities Involving Reciprocals of Triangle Areas by Yakub N. Aliyev 36.8
• On a Problem Concerning Two Conics by Aleksander Simonic 38.9
• On Some Examples of Geometric Fallacies by Toshio Seimiya 29.6
• On the Generalized Ptolemy Theorem by Shailesh Shirali 22.2
• One Problem - Six Solutions by Georg Gunther 24.2
• Pythagoras Strikes Again! by K.R.S. Sastry 24.5
• Tangent circles in the ratio 2 : 1 by Hiroshi Okumura & Masayuki Watanabe 27.2
• The Converse of Schiffler's Theorem by Joe Goggins 33.6
• The Diagonal Points of a Cyclic Quadrangle by Christopher J. Bradley 31.3
• The Power of Symmetry, An Example Linking Algebra and Geometry by Nicholea Gusita & Michael Silbert 29.8
• The Triangle, A Parametric Description by K.R.S. Sastry 30.8 
• Velocity Analysis, an Approach to Solving Geometry Problems by  Peng YuChen  35.1.

Recurring Crux Configurations, by J. Chris Fisher

1. Triangles for which $2b^2 = c^2 + a^2$ 37.5  
2. Triangles for which $2b = c + a$  37.6
3. Triangles whose angles satisfy $2B = C + A$ 37.7
4. Bicentric Quadrilaterals 37.8
5. Cyclic Orthodiagonal Quadrilaterals 38.2
6. Triangles for Which OI Is Parallel to a Side 38.4
7. Triangles whose angles satisfy $B = 2C$  38.6
8. Heronian Triangles 38.8
9. Triangles Whose Angles Satisfy $B = 90^o + C$ 38.10

Focus On .., by Michel Bataille 

• 04. Barycentric Equation of line  38.9

History

• F.G.-M. Mystery solved  by Paul Yiu 26.8 

Geometry Articles by Mathematical Reflections (collected here)

1. A Characterization of the Parallelogram, by Paris Pamfilos 2016.3
2. A Fine Use of Transformations, by Rithvik Pasumarty 2016.4
3. A Forgotten Coaxality Lemma, by Stanisor Stefan Dan 2015.5
4. A Generalization of the Napoleon’s Theorem, by Khakimboy Egamberganov 2017.3
5. A Metric Relation and its Applications, by Son Hong Ta 2008.2
6. A minimum problem, by Laurentiu Panaitopol 2006.6
7. A new proof for Napoleon's Theorem, by Alex Anderson  2007.3
8. A Note on Power of a Point, by Michal Rolinek & Josef Tkadlec 2010.5
9. A Nice Theorem on Mixtilinear Incircles, by Khakimboy Egamberganov 2016.4
10. A Note on the Malfatti Problem, by Titu Andreescu & Oleg Mushkarov 2006.4
11. A Short Proof of Lamoen's Generalization of the Droz-Farny Line Theorem, by Cosmin Pohoata & Son Hong Ta 2011
12. A Special Point on the Median, by Anant Mudgal & Gunmay Handa 2017.2
13. A Way to Prove a Geometric Inequality R $\ge$ 3r, by Nguyen Tien Lam 2009.1
14. All About Excircles!, by Prasanna Ramakrishnan 2014.6
15. Angle Inequalities in Tetrahedra, by Mark Chen 2008.6
16. Back to Euclidean Geometry: Droz-Farny Demystified, by Titu Andreescu & Cosmin Pohoata 2012
17. Concyclicities in Tucker-like Configurations, by Stefan Dominte & Tudor-Dimitrie Popescu 2016.1
18. Droz-Farny, an Inverse View, by Paris Pamfilos 2015.2
19. Equiangular polygons: An algebraic approach, by Titu  Andreescu & Bogdan Enescu 2006.1
20. Harmonic Division and its Applications, by Cosmin Pohoata 2007.4
21. Inequalities on Ratios of Radii of Tangent Circles, by Y.N. Aliyev 2015.5
22. From Baltic Way to Feuerbach - A Geometrical Excursion, by Darij Grinberg 2006.2
23. Hartcourt’s Theorem Via Salmon’s Lemma, by Luis Gonzalez and Cosmin Pohoata 2013.6
24. How to make a soccer ball, Euler's relation for polyhedra and planar graphs, by Bogdan Enescu 2013.4
25. Let's Talk About Symmedians! , by Sammy Luo and Cosmin Pohoata 2013.4
26. Newton and Midpoints of Diagonals of Circumscriptible Quadrilaterals, by Titu  Andreescu, Luis Gonzalez & Cosmin Pohoata 2014.1
27. On a Mixtilinear Coaxality, by Cosmin Pohoata & Vladimir Zajic 2012
28. On a vector equality, by Nguyen Tien Lam 2008.6
29. On Casey's Inequality, by Tran Quang Hung 2011.2
30. On Distances In Regular Polygons, by N. Javier Buitrago A. 2010.5
31. On Fontene’s Theorems, by Marius Bocanu  2015.2
32. On some geometric inequalities, by Tran Quang Hung 2008.3
33. On the area of a pedal triangle, by Ivan Borsenco 2007.2
34. On the extension of Carnot's Theorem, by Tran Quang Hung 2007.6
35. On the Maximum Area of a Triangle With the Fixed Distances From its Vertices to a Given Point , by Ivan Borsenco, Roberto Bosch Cabrera & Daniel Lasaosa 2014.2
36. On vector properties of an equilateral triangle, by Tran Quang Hung 2007.2
37. Similar Quadrilaterals, by Guangqi Cui, Akshaj Kadaveru, Joshua Lee, Sagar Maheshwari 2014.5
38. The Apollonian Circles and Isodynamic Points, by Tarik Adnan Moon 2010.6
39. The Monge-D’Alembert Circle Theorem, by Cosmin Pohoata & Jan Vonk 2011.5
40. The Neuberg-Mineur circle, by Darij Grinberg 2012
41. The Symmedian Point and Poncelet’s Porism, by Luis Gonzales and Cosmin Pohoata  2012
42. Triangle Bordered With Squares, by Catalin Barbu 2010.4
43. Triangles Homothetic with the Intouch Triangle, by Sava Grozdev, Hiroshi Okumura, & Deko Dekov 2018.2
44. Vectors Conquering Hexagons, by Iurie Boreico 2008.1

Geometry Articles by Mathematical Excalibur (collected here)

by Kin - Yin Li

• A Geometry Theorem Vol.16 No. 4 (Subtended Angle Theorem)
• Angle Bisectors Bisect Arcs Vol.11 No. 2
• Casey’s Theorem Vol.16 No. 5 
• Cavalieri’s Principle Vol.5 No. 1
• Concyclic Problems  Vol.6 No. 1
• Coordinate Geometry Vol.5 No. 3
• Famous Geometry Theorems Vol.10 No. 3 (Brianchon, Desargues, Menelaus, Newton, Pascal)
• Geometric Transformations I Vol.13 No.2 (translation, rotation, reflection, spiral similarity)
• Geometric Transformations II Vol.13 No.3 (translation, homothety, rotation, reflection)
• Geometry via Complex Numbers Vol.9 No.1
• Homothety Vol.9 No.4
• Inversion Vol.9 No.2
• Similar Triangles via Complex Numbers Vol.1 No.3
• Perpendicular Lines Vol.12 No. 3
• Pole and Polar Vol.11 No. 4
• Polygonal Problems Vol.19 No. 4
• Power of Points Respect to Circles  Vol.4 No.3
• Ptolemy's Theorem  Vol.2 No.4
• Vector Geometry Vol.6 No. 5

by K. K. Kwok

• From How to Solve It to Problem Solving in Geometry I  Vol.12 No.1
• From How to Solve It to Problem Solving in Geometry II Vol.12 No.2

by Nguyen Ngoc Giang

• Ptolemy’s Inequality Vol.18 No.1

Geometry Articles  by  Revista Escolar de la Olimpíada Iberoamericana de Matemática (collected here)

Original

• Batinetu-Giurgiu & Neculai Stanciu  Una nueva demostración de la desigualdad de Euler Νο.58 
• Carlos A. Gomes Uma soma incrivilmente invariante Νο. 20 (Carnot)
• Castiñeira Merino, Julio Circunradio y volumen de poliedros. Νο.52
• Cristóbal Sánchez-Rubio García Nueve caracterizaciones de los triángulos cuyos lados están en progresión aritmética. No.40 
• Donaire Peña, Milton F. Una prueba elemental del teorema de Pascal.  No.39
• Durán Cepeda, Darío Soluciones elementales a problemas elementales. Νο.52
• Evgeniy Kulanin y Alexei Myakishev Algunas cónicas relacionadas con el triángulo Νο. 42
• Francisco Bellot Rosado Los teoremas de Ptolomeo y su generalización por Casey. Aplicaciones No.01 
• Francisco Bellot Rosado La cuchilla de zapatero No.06 (Arbelos)
• Francisco Bellot Rosado Algunas aplicaciones de la noción de área: el triángulo de Routh y los triángulos cevianos. Νο.15
• Francisco Bellot Rosado Terminología de la geometría del triángulo Νο.17
• Francisco Bellot Rosado Triángulos especiales (I) Νο.17
• Francisco Bellot Rosado Triángulos especiales (2) Νο.18
• Francisco Bellot Rosado Triángulos especiales III  Νο.19
• Francisco Bellot Rosado Geometría del tetraedro Νο.32
• Francisco Bellot Rosado Albrecht Hess: Nuevas soluciones a los “Problemas de Geometría de Olimpiadas”   Νο.40
• Francisco J. García Capitán Inversión en Olimpiadas (Aplicación de la inversión a la resolución de problemas) No.27
• Francisco J. García Capitán Lectura atenta del libro "College Geometry", de Nathan Altshiller Court (1). No.32
• Francisco J. García Capitán Lectura atenta del Court (2): el triángulo órtico   No. 37
• Francisco J. García Capitán Ángulos e inversión Νο.54
• Francisco J. García Capitán Un problema del Sidler. No.56
• Francisco J. García Capitán Algunas homografías en el triángulo No.57
• Francisco J. García Capitán Máximos sin derivadas Νο. 58
• Juan Carlos Salazar El Teorema de Harcourt  No.08
• Juan Carlos Salazar Relación del ortocentro de un triángulo. Νο.12
• Juan Carlos Salazar Algunos teoremas y sus demostraciones. Νο.13 (Fuss, Gergonne-Anne, Japanese)
• Juan M. Conde El teorema de Morley Νο.14
• Jean-Louis Ayme Algunos teoremas olvidados. No.10
• Jean-Louis Ayme El ortocentro del triángulo de Fuhrmann. No.23
• Jean-Louis Ayme El teorema de Feuerbach: una demostración puramente sintética. No.26
• Jean-Louis Ayme El teorema de Sondat No.29
• Jean-Louis Ayme El teorema de Reim viaja. Νο. 58
• K.R.S. Sastry Pares de triángulos heronianos con el mismo perímetro y la misma área: una descripción. Νο.16
• K.R.S. Sastry Triángulos armónicos,   No.25
• M. Álvarez, G. González, E. Pérez Almarales Los vectores: una de las vías fundamentales para el vínculo interconeptual entre las disciplinas de Álgebra y Geometría en problemas de Olimpiadas. Νο. 49
• Miguel Amengual Covas La desigualdad de Euler a partir de otras desigualdades entre elementos de un triángulo. No.05
• Miguel Amengual Covas La desigualdad de Euler (2ª parte)  No.09

Translated in Spanish

• Abderrahim Ouardini Máximos y mínimos sin derivación. Tres ejemplos  No.03
• C.Rusu: Distancia de un punto del espacio a un punto en el plano de un triángulo. Νο.55
• P. Lapôtre Problemas de Agrimensores y constructores de Catedrales  Νο.54
• Lasters, Guido y Staelens, Hugo :Hablando de cuadrados negativos…  No.39

Geometry material from Canada IMO Training Site (collected here) (source:https://sites.google.com/site/imocanada/)

Adrian Tang

• Combinatorics and Combinatorial Geometry, 2009 winter

Alexander Remorov

• Projective Geometry, Solutions 2010 summer
• Projective Geometry Continued (Solutions) 2010 summer

David Arthur

• Geometry Fundamentals 2011 winter
• Geometry - Length Chasing 2015 summer

Matthew Brennan

• Combinatorial Geometry 2019 winter
• Miscellaneous Geometry Facts 2017 winter
• Geometry (Some Tricks in Synthetic Geometry) 2017 winter 

Lindsey Shorser

• Projective Geometry   2015 summer 

Yufei Zhao

• Circles 2008 summer
• Cyclic Quadrilaterals - The Big Picture, 2009 winter
• Geometry 2008 summer (Selected Geometry Problems from Recent IMO Shortlists)
• Lemmas in Euclidean Geometry (Problem set)  2007 summer.pdf 
• Lemmas in Euclidean Geometry 2007 summer
• Similarity - Yufei Zhao - 2007 summer
• Three Lemmas in Euclidean Geometry (Solutions), 2010 Winter
• Power of a Point (Solutions) - UK Trinity Training 2011 (Mint group) [the only non Canada IMO training material in this page]

Victoria Krakovna

• ArealCoordinates_1998summer
• CircleProblemsCMO_2001winter
• Concurrency and Collinearity 2010 summer
• GeometryProblemsForFunAndProfit_1998summer
• Geometry Problems for Fun and Profit - 2005 winter 
• Geometry_IfYoureBored_2004winter
• GeometryProblems_1998summer
• GeometryProblemsTournamentOfTowns_2000winter
• GeometryProblems_2000winter
• GeometryProblems_2001winter
• Geometry_2003winter
• Geometry2_2003winter
• Geometry_2004winter
• Geometry2_2004winter
• Geometry Problems - 2005 winter
• Geometry Problems (Hard) - 2005 winter
• GeometryReview_2000winter (theory)
• GeometryTheoremsList_1998summer  (theory)
• InversionProblems_1998summer
• Inversion_2002winter
• LocusHocusPocus_1998summer
• Rotations and Harmonic Points, 2010 winter
• SimilarTriangles_2000winter
• Problems list by type - 2005 summer
• TrainingProblems4_1998summer  (closed, convex, possible)
• Transformations_1999winter

2018 winter camp

• Geometry (Rotations and Inversion)

Finally

The problems from the Facebook Group Romantics of Geometry in English:

 
plane geometry links in FB: 001-500, 501-1000, 1001-1500 , 1501-2000 , 2000-2500
link in FB: solid geometry

The exercises by the Romantics of Geometry in English (pdf): (not updated anymore)

• 120 geometry exercises by Romantics of Geometry, volume 1, issues 01-10, No 001-120 (12.11.2016) 
• 60 geometry exercises by Romantics of Geometry,  issues 11-15, No 121-180 (08.03.2017)
• 24 geometry exercises by Romantics of Geometry,  issues 36-37, No 421-444 (08.03.2017)
• 12 geometry exercises by Romantics of Geometry,  issue 46, No 541-552 (07.03.2017)