Deficiency Diseases and Good Nutrition - Phosphorus - Details the location and function of phosphorus in the body, the similarity to calcium deficiency, and foods high in this mineral. - http://waltonfeed.com/self/health/vit-min/phos.html
Hypophosphatemia - Brief Wikipedia article discusses this imbalance, its causes, and pathophysiology. - http://en.wikipedia.org/wiki/Hypophosphatemia
eMedicine: Hypophosphatemia - Clinical article details what are low levels and why phosphate is important to bones, DNA, and cellular function. Includes causes, symptoms, treatment, and medications. - http://www.emedicine.com/med/topic1135.htm