Crawford, R. (1987). Plastics Engineering R.j. Crawford. Pergamon.
Lua i Stíl Chicago (17ú heag.)Crawford, R.J. Plastics Engineering R.j. Crawford. Pergamon, 1987.
Lua MLA (8ú heag.)Crawford, R.J. Plastics Engineering R.j. Crawford. Pergamon, 1987.
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