@article{Lexis1878,
author = {Lexis, W.},
title= {Sur la duree normale de la vie humaine et sur la theorie de la stabilite des rapports statistiques [On the normal human lifespan and on the theory of the stability of the statistical ratios]},
year = {1878},
journal = {Annales de Demographie Internationale},
volume = {2},
pages = {447--460},
}