Author: Margarit Iliev
fertility
37. Investigation on egg fertility and hatchability in ostriches (Struthio camelus)
Author: Matina Nickolova
7. Geodemographic characteristics of the sexual and age structure in the region of Lovech over the 2011/2013 period
Author: Desislav Petrov, Petar Marinov
8. Analysis of the natural growth of the population in the South-Central Region for the 2008/2013 period
Author: Peter Marinov