527,036 WOODFORD F.PETER /red./ Behaviour modification with the severely retarded. Ed. by C.C.Kiernan and P.Peter Woodford. Amsterdam 1975 Elsevier, Excerpta Medica, Korth-Jfolland 80 s. VIII, nib. 2, 332. IRMM [lnstitute for Research into Mental and Multiple Handicap] Study Group 8