Hladnik U, Nyhan WL, Bertelli M (septiembre de 2008). «Variable expression of HPRT deficiency in 5 members of a family with the same mutation». Arch. Neurol.65 (9): 1240-3. PMID18779430. doi:10.1001/archneur.65.9.1240.
Hladnik U, Nyhan WL, Bertelli M (septiembre de 2008). «Variable expression of HPRT deficiency in 5 members of a family with the same mutation». Arch. Neurol.65 (9): 1240-3. PMID18779430. doi:10.1001/archneur.65.9.1240.