Alberto M. Dou. Logical and historical remarks on Saccheri's geometry. Notre Dame Journal of Formal Logic, 11(4):385-415, 1970. [doi]
@article{Dou70,
title = {Logical and historical remarks on Saccheri's geometry},
author = {Alberto M. Dou},
year = {1970},
doi = {10.1305/ndjfl/1093894070},
url = {http://dx.doi.org/10.1305/ndjfl/1093894070},
researchr = {https://researchr.org/publication/Dou70},
cites = {0},
citedby = {0},
journal = {Notre Dame Journal of Formal Logic},
volume = {11},
number = {4},
pages = {385-415},
}