Kiselyov's geometry
The book is a unique phenomenon in Russian geometry education. It was first published in 1892; there have been more than 40 revised editions, and dozens of millions of copies (by these parameters, it is trailing only Euclid's Elements). Our edition is based on the 41st edition (the stable edition of Nil Aleksandrovich Glagolev; it's been in public domain since 2015). In a few places, we reverted changes; we also made more accurate historical remarks.
math.HO↗