MADDOX, R. (1977). Gas and liquid sweetening - R.N.Maddox. Campbell Petroleum Series.
Lua i Stíl Chicago (17ú heag.)MADDOX, R.N. Gas and Liquid Sweetening - R.N.Maddox. Campbell Petroleum Series, 1977.
Lua MLA (8ú heag.)MADDOX, R.N. Gas and Liquid Sweetening - R.N.Maddox. Campbell Petroleum Series, 1977.
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