Einspahr, H.; Bugg, C. E. (1981). "The geometry of calcium carboxylate interactions in crystalline complexes". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry. 37 (5): 1044–1052. Bibcode:1981AcCrB..37.1044E. doi:10.1107/S0567740881005037.
Einspahr, H.; Bugg, C. E. (1981). "The geometry of calcium carboxylate interactions in crystalline complexes". Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry. 37 (5): 1044–1052. Bibcode:1981AcCrB..37.1044E. doi:10.1107/S0567740881005037.