ZHANG, Ruda July 31, 2021:  Add uppercase greek letters that coincide with the latin alphabet. [3d8b7f1]
ZHANG, Ruda March 09, 2021:  Defind mode, median; more on Gaussian rv, probabilistic models on matrix manifolds. [7c5a23c]
ZHANG, Ruda May 14, 2019:  Add Math Characters. [cb01b74]