Jacobs H , Niemann A , Kockelmann W , Zeitschrift fur Anorganische und Allgemeine Chemie , 631 (2005) p.1247-1254, Low temperature investigations of hydrogen bridge bonds in the hydroxides, beta-Be(OH)2 and epsilon-Zn(OH)2 by Raman-spectroscopy as well as X-ray and neutron diffraction, Locality: synthetic, Sample: T = 50 K