rs. 2013-07-26 [2022-01-21]. (原始内容存档于2019-07-03). Roser, Max, Total Fertility Rate around the world over the last centuries, Our World In Data, Gapminder
activity in male impala, Aepyceros melampus. Journal of Reproduction and Fertility. 1972, 31 (1): 77–81. PMID 5078117. doi:10.1530/jrf.0.0310077 (英语). Mooring