1. Where have all the conceptions gone?;C Roberts;Lancet.,1975
2. Survival probability of human conceptions from fertilization to term.;C Boklage;Int J Fertil.,1990
3. Intrauterine Mortality;H Leridon,1977
4. Thirty-four fertilized human ova, good, bad and indifferent, recovered from 210 women of known fertility; a study of biologic wastage in early human pregnancy.;A Hertig;Pediatr.,1959
5. The Overall Problem in Man.;A Hertig,1967