સ્ફટિક: આવૃત્તિઓ વચ્ચેનો તફાવત

*{{cite web|author=Various authors|title=Crystal Lattice Structures:Index by Space Group|url=http://cst-www.nrl.navy.mil/lattice/spcgrp/|year=2004|accessdate=2008-04-20|publisher=[[U.S. Naval Research Laboratory]], Center for Computational Materials Science}}

*{{cite web|author=Various authors|title=Crystallography|url=http://www.xtal.iqfr.csic.es/Cristalografia/index-en.html|year=2010|accessdate=2010-01-08|publisher=[[Spanish National Research Council]], Department of Crystallography}}