1. Arnold TW (1994) Effects of supplemental food on egg production in American coots. Auk 111:337–350
2. Blount JD, Houston DC, Surai PF, Møller AP (2004) Egg-laying capacity is limited by carotenoid pigment availability in wild gulls Larus fuscus. Proc Roy Soc Lond Bio 271[Supp 1]:S79–S81
3. Boutin S (1990) Food supplementation experiments with terrestrial vertebrates: patterns, problems, and the future. Can J Zool 68:203–220
4. Catalan RM, Haeger JF (1996) Breeding patterns of the great tit (Parus major) in a pine plantation and a holm oak forest in a Mediterranean region (southern Spain). Rev Ecol-Terre Vie 51:341–357
5. Cichoń M (1997) Egg weight variation in Collared Flycatchers Ficedula albicollis. Ornis Fenn 74:141–147