=LDR 22 4500 =001 6442 =082 04$a519.8 WAL =100 1\$aWalsh, G.R. =245 10$aMethods of Optimization =260 \\$aChichester :$bWiley,$c1975 =650 \0$aBooks =852 \\$bGeography Basement$h519.8 WAL