APA

Zorbalas K., Wintershall Ag, INGEPET '99 I. S. (. . 1. O. 2. . L. P. & Wintershall Ag.Comparing investment efficiencies for oil and gas prospects in South America. : .

Chicago

Zorbalas Konstantino, Wintershall Ag, INGEPET '99 International Seminar (3° 1999 Oct 26-29 Lima Perú) and Wintershall Ag.Comparing investment efficiencies for oil and gas prospects in South America. : .

Harvard

Zorbalas K., Wintershall Ag, INGEPET '99 I. S. (. . 1. O. 2. . L. P. and Wintershall Ag.Comparing investment efficiencies for oil and gas prospects in South America. : .

MLA

Zorbalas Konstantino, Wintershall Ag, INGEPET '99 International Seminar (3° 1999 Oct 26-29 Lima Perú) and Wintershall Ag.: . .