@inbook{Beard1959,
author = {Beard, R.E.},
title= {Appendix: Note on some mathematical mortality models},
year = {1959},
doi = {10.1002/9780470715253.app1},
editor = {Wolstenholme, G.E.W.},
editor = {O’Connor, M.},
booktitle = {The lifespan of animals. CIBA Foundation Colloquium on Ageing},
address = {Boston},
publisher = {Little, Brown},
pages = {302--311},
}