Drummond, Hugh; Edda Gonzalez; Jose Luis Osorno (1986). "Parent-Offspring Cooperation in the Blue-footed Booby (Sula nebouxii): Social Roles in Infanticidal Brood Reduction". Behavioral Ecology and Sociobiology. 19 (5): 365–372. Bibcode:1986BEcoS..19..365D. doi:10.1007/bf00295710. S2CID36417383.
Drummond, Hugh; Edda Gonzalez; Jose Luis Osorno (1986). "Parent-Offspring Cooperation in the Blue-footed Booby (Sula nebouxii): Social Roles in Infanticidal Brood Reduction". Behavioral Ecology and Sociobiology. 19 (5): 365–372. Bibcode:1986BEcoS..19..365D. doi:10.1007/bf00295710. S2CID36417383.
Drummond, Hugh; Edda Gonzalez; Jose Luis Osorno (1986). "Parent-Offspring Cooperation in the Blue-footed Booby (Sula nebouxii): Social Roles in Infanticidal Brood Reduction". Behavioral Ecology and Sociobiology. 19 (5): 365–372. Bibcode:1986BEcoS..19..365D. doi:10.1007/bf00295710. S2CID36417383.
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