00361nam a22001337a 450000500170000000800410001702000080005804100080006608200170007410000180009124500470010926000560015630000150021220260421110051.0260421b        |||||||| |||| 00| 0 eng d  a000  aeng  a591.3bLAN/T  aLanger, Jonas  aTheories of Developmentc/ by Jonas Langer  aNew York:bHolt, Rinehart and Winston, INC, c1969.  axi, 191p.;