@article{104789,
author = {Robert Karpe},
title = {Verallgemeinerung der goniometrischen Funktionen},
journal = {Archivum Mathematicum},
volume = {009},
year = {1973},
pages = {26-48},
zbl = {0282.50004},
mrnumber = {0362007},
language = {de},
url = {http://dml.mathdoc.fr/item/104789}
}
Karpe, Robert. Verallgemeinerung der goniometrischen Funktionen. Archivum Mathematicum, Tome 009 (1973) pp. 26-48. http://gdmltest.u-ga.fr/item/104789/
O rovnicích, Praha, r. 1947. (1947)