Batten, T.R.
The human factor in youth work / T.R. Batten eith the collaboration of Madge Batten
Oxford University Press, 1970
 Buku Teks SO
Doxiadis, C.A.
The human settlements that we need
Tata McGraw-Hill, 1976
 Buku Teks SO
The 1973 [one thousand nine hundred seventy-three] annual handbook for group facilitators
Edited by John E. Jones and J. William Pfeiffer
University Associates, 1973
 Buku Teks SO
The 1974 (one thousand nine hundred seventy four) annual handbook for group facilitators
Edited by J. William Pfeiffer and John E. Jones
University Associates, 1974
 Buku Teks SO
The 1976 [one thousand nine hundred seventy-six] annual handbook for group facilitators: the fifth annual
Edited by J. William Pfeiffer and John E. Jones
University Associates, 1976
 Buku Teks SO