TY  - BOOK
AU  - Crosby,Muriel Estelle
TI  - Supervision as co-operative action
AV  - LB2822.5 .C7
U1  - 371.2 
PY  - 1957///]
CY  - New York
PB  - Appleton-Century-Crofts
KW  - School supervision, Elementary
KW  - Local
N1  - Includes bibliographical references
ER  -