APA

(1986). Colombia Exporta - Vol.5 No.24,23,22,21,20,19. : .

Chicago

1986. Colombia Exporta - Vol.5 No.24,23,22,21,20,19. : .

Harvard

(1986). Colombia Exporta - Vol.5 No.24,23,22,21,20,19. : .

MLA

Colombia Exporta - Vol.5 No.24,23,22,21,20,19. : . 1986.