Balsa, Raúl E.; Ingratta, Stella Maris; Alvarez, Alberto G. (1986). "Acquired kinking of the hair: A methodologic approach". Journal of the American Academy of Dermatology. 15 (5). Elsevier BV: 1133–1136. doi:10.1016/s0190-9622(86)70281-8. ISSN0190-9622. PMID3771867.
Balsa, Raúl E.; Ingratta, Stella Maris; Alvarez, Alberto G. (1986). "Acquired kinking of the hair: A methodologic approach". Journal of the American Academy of Dermatology. 15 (5). Elsevier BV: 1133–1136. doi:10.1016/s0190-9622(86)70281-8. ISSN0190-9622. PMID3771867.
Balsa, Raúl E.; Ingratta, Stella Maris; Alvarez, Alberto G. (1986). "Acquired kinking of the hair: A methodologic approach". Journal of the American Academy of Dermatology. 15 (5). Elsevier BV: 1133–1136. doi:10.1016/s0190-9622(86)70281-8. ISSN0190-9622. PMID3771867.