Mortier, A., Lemaitre, J., Rodrique, L., & Rouxhet, P. (1989). Synthesis and Thermal-behavior of Well-crystallized Calcium-deficient Phosphate Apatite. Journal of Solid State Chemistry, 78(2), 215-219. https://doi.org/10.1016/0022-4596(89)90099-6 (Original work published 1989)