2657 251 10 Ramon J. Aldag Additional Author Timothy M. Stearns Additional Author mixed material 0538077026 Amerika South Western Publishing 1987 William H. Mason Additional Author Norton L. Marshall Additional Author mixed material 006044245x New York. Harper & Row 1987 Ruthann Corwin, dkk Additional Author mixed material 0877350612 Amerika Freeman, Cooper & Company 1975 Practice in Thinking mixed material 0829903720 New York. West Publishing 1981 Joel R. Evans Additional Author Barry Berman Additional Author mixed material 0023344105 Amerika Macmillan Publiing 1987 Malcolm B. Carpenter Additional Author mixed material 0683014552 Sydney Wiolliams 1985 mixed material 0864330553 Lonon Maclennan Petty 1990 An Ecologist's Account of the Extinction of a Species Anne LaBastille Additional Author mixed material 0393028305 London WW.Norton & Company 1990 B.R. Sharma Additional Author mixed material New Delhi Satya Prakashan 1976 mixed material 0803925301 Amerika Sage Publications 1986