LONGMAN. (1983). Financial times oil and gas international year book 1983. Longmans Inc.
Dyfyniad Arddull ChicagoLONGMAN. Financial Times Oil and Gas International Year Book 1983. Longmans Inc, 1983.
Dyfyniad MLALONGMAN. Financial Times Oil and Gas International Year Book 1983. Longmans Inc, 1983.
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