RT Journal Article SR Electronic T1 The nosology of the spinal muscular atrophies. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 481 OP 495 DO 10.1136/jmg.8.4.481 VO 8 IS 4 A1 A E Emery YR 1971 UL http://jmg.bmj.com/content/8/4/481.abstract AB