Danielsbacka M, Tanskanen A, Jokela M, Rotkirch A. Grandparental child care in Europe: Evidence for preferential investment in more certain kin. Evolutionary Psychology, 2011; 9: 3-24.
Danielsbacka M, Tanskanen A, Jokela M, Rotkirch A. Grandparental child care in Europe: Evidence for preferential investment in more certain kin. Evolutionary Psychology, 2011; 9: 3-24.