Viro, Julia Drobotukhina; Viro, Oleg (1990), "Configurations of skew lines"(PDF), Leningrad Math. J. (in Russian), 1 (4): 1027–1050, archived from the original(PDF) on 2021-11-09, retrieved 2006-10-24. Revised version in English: arXiv:math.GT/0611374
uu.se
math.uu.se
Viro, Julia Drobotukhina; Viro, Oleg (1990), "Configurations of skew lines"(PDF), Leningrad Math. J. (in Russian), 1 (4): 1027–1050, archived from the original(PDF) on 2021-11-09, retrieved 2006-10-24. Revised version in English: arXiv:math.GT/0611374
web.archive.org
Viro, Julia Drobotukhina; Viro, Oleg (1990), "Configurations of skew lines"(PDF), Leningrad Math. J. (in Russian), 1 (4): 1027–1050, archived from the original(PDF) on 2021-11-09, retrieved 2006-10-24. Revised version in English: arXiv:math.GT/0611374
