This paper traces the history of the two-piece normal distribution from its origin in the posthumous Kollektivmasslehre (1897) of Gustav Theodor Fechner to its rediscoveries and generalisations. The denial of Fechner’s originality by Karl Pearson, reiterated a century later by Oscar Sheynin, is shown to be without foundation.
"The Two-Piece Normal, Binormal, or Double Gaussian Distribution: Its Origin and Rediscoveries." Statist. Sci. 29 (1) 106 - 112, February 2014. https://doi.org/10.1214/13-STS417