L. Salazar - C. Navarro, Santillana
$4.80
Gaceta No. 39.627, Ml
$8.00
Gaceta Nº 38.596, Njr
$2.85
Roberto H. Frank, Mcgraw Hill
$32.00
Frederick Cabrera Conde, Ediciones Mutare
$10.00
Cesar Borobia, Elsevier
$29.20
Gaceta Nº 39.808, Njr
$2.00