@inbook{402756,
title = {Dvoj\'\i\ geometrie},
booktitle = {Z\'aklady neeukleidovsk\'e geometrie Loba\v cevsk\'eho},
series = {GDML\_Books},
publisher = {P\v r\'\i rodov\v edeck\'e nakladatelstv\'\i },
address = {Praha},
year = {1953},
pages = {88-105},
url = {http://dml.mathdoc.fr/item/402756}
}
(éd.). Dvojí geometrie, dans Základy neeukleidovské geometrie Lobačevského, GDML_Books, (1953), pp. 88-105. http://gdmltest.u-ga.fr/item/402756/