Plodnosc i nieplodnosc zwierzat domowych. VII. Referaty V konferencji delegatow Akademii Nauk krajow RWPG, KOMITET Nauk. weterynaryjnych PAN oraz Instytut Zootechniki, Krakow, 23--28 wrzesien 1968 | Fertility and infertility in domestic animals. VII. Papers of the V conference of the delegates of the academies of sciences from the countries of the Council for Mutual Economic Assistance, the Committee for Veterinary Sciences of the Polish Academy of Sciences, and the Institute for Zootechnology, held in Cracow, September 23-28, 1968