00463nam a2200157Ia 4500 0000014617 20251012174532.0 s1968 xx c 262130386 eng Z678 .M67 1968 Library effectiveness a systems approach Philip M Morse Cambridge Massachusetts Institute of Technology Press 1968 p. Library science Mathematical models 5572 5572 0 0 0 0 KEM KEM 2012-12-07 0 0000006477 2025-10-12 08:35:34 2025-10-12 OS