Specification 93
editor, Alan Williams
Emap Architecture, 1993
 Buku Referensi
Specification 93 clauses
editor, Alan Williams
Emap, 1993
 Buku Referensi
Specification 93 Technical
edited by Alan Williams
Emap, 1993
 Buku Referensi
Willis, Claire
Abstraction and specification with modula-2
Pitman, 1992
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Rosa, Frank
Water treatment specification manual
McGraw-Hill, 1985
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