BIJLSMA RG (1996) Book reviews:Graveland, J., The quest for calcium, 1995. Proefschrift Groningen. LIMOSA 69 (1): 31-32.

GRAVELAND J. 1995. The quest for calcium. Calcium limitation in the reproduction of forest passerines in relation to snail abundance and soil acidification. Proefschrift, Rijksuniversiteit van Groningen, Groningen. 171 p. ISBN 90.9008.131.3.

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