Forschungen, Institut für kunst-und musikhistorische (2002). "Glockenguss". ISBN 978-3-7001-3043-7 (in German). Retrieved 2022-10-28.
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National Research Council, 1976, Fat Content and Composition of Animal Products, Printing and Publishing Office, National Academy of Science, Washington, D.C., ISBN0-309-02440-4; p. 203, online edition