ISSN 1551-8833 ↑ "Drinking Water Hardwater Hardness Calcium Magnesium Scale Stained Laundry". Water-research.net. Retrieved 2013-01-26. ↑ František Kožíšek Health significance of drinking water calcium and magnesium, February 2003 ↑ Pocock SJ, Shaper AG, Packham RF (April 1981).