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D'ors, Pablo Perez; Johnson, Richard (2012). «Velazquez in Fraga: a new hypothesis about the portraits of El Primo and Philip IV». The Burlington Magazine. 154 (1314). p. 623. JSTOR41812780
D'ors, Pablo Perez; Johnson, Richard (2012). «Velázquez in Fraga: a new hypothesis about the portraits of El Primo and Philip IV». The Burlington Magazine. 154 (1314). p. 622. JSTOR41812780
D'ors, Pablo Perez; Johnson, Richard (2012). «Velázquez in Fraga: a new hypothesis about the portraits of El Primo and Philip IV». The Burlington Magazine. 154 (1314). p. 624. JSTOR41812780
D'ors, Pablo Perez; Johnson, Richard (2012). «Velázquez in Fraga: a new hypothesis about the portraits of El Primo and Philip IV». The Burlington Magazine. 154 (1314). p. 625. JSTOR41812780