Reference

Elisabeth Söderlund, David J. Rowcliffe, Erland Dannelid (1992): On the hardness of pigmented and unpigmented enamel in teeth of shrews of the genera Sorex and Crocidura (Mammalia, Soricidae) – Mammalian Biology (früher Zeitschrift für Säugetierkunde) – 57: 321 - 329.