#BOTD: Nikolai Ivanovich Lobachevsky.
"Nikolai Lobachevsky published his work on non-Euclidean geometry, the first account of the subject to appear in print." https://mathshistory.st-andrews.ac.uk/Biographies/Lobachevsky/ #OTD #History #Maths #Math #Mathematics #STEM #Geometry @science
