000 00263nam a2200085 4500
080 _a025.4
_bPER.69
245 _aTowards a theory for UDC; essays aimed at structural understanding and operational improvement
100 _aPerreault, J.M
260 _aLondon
_bClive Bingley
_c1969
300 _a241p
999 _c27845
_d27845