61. Another interpretative position in relation to Article 26 is addressed at granting full effectiveness to economic, social and cultural rights. This school of thought is the one that, for some time, has been defended by an important sector of legal doctrine in order to accord this treaty-based article normative nature, as the Inter-American Court did in the Case of Acevedo Buendía v. Peru in 2009, constituting a firm step in that direction, and abandoning the precedent of the 2005 Case of the Five Pensioners v. Peru. 102 62. For some, the rights protected by Article 26 of the American Convention are those derived from the economic, social, educational, scientific and cultural norms contained in the OAS Charter, without any possibility of referral to the American Declaration. 103 Once it has been determined that a rights is implicit in the Charter and, therefore, included in Article 26, it can then be interpreted with the aid of the American Declaration or of other human rights treaties in force in the respective State. 104 On the other hand, it is also affirmed that, in addition to the pro persona principle, in order to know which rights are derived from the goals established in the OAS Charter, it is necessary to resort to other international instruments, such as the American Declaration, constitutional texts, and the work of international monitoring mechanisms. 105 63. Regarding the possible integration of the OAS Charter with the American Declaration on the Rights and Duties of Man, it is pertinent to take into account Advisory Opinion OC10/89 “Interpretation of the American Declaration on the Rights and Duties of Man within the framework of Article 64 of the American Convention on Human Rights”, of July 14, 1989, especially paragraphs 43 and 45: 43. Hence it may be said that by means of an authoritative interpretation, the Member States of the Organization have signaled their agreement that the Declaration contains and defines the fundamental human rights referred to in the Charter. Thus the Charter of the Organization cannot be interpreted and applied as far as human rights are concerned without relating its norms, consistent with the practice of the organs of the OAS, to the corresponding provisions of the Declaration. […] 45. For the Member States of the Organization, the Declaration is the text that defines the human rights referred to in the Charter. Moreover, Articles 1(2)(b) and 20 of the Commission's Statute define the competence of that body with respect to the human rights enunciated in the Declaration, with the result that, to this extent, the American Declaration is for these States a source of international obligations related to the Charter of the Organization. 102 Regarding the critiques of this judgment, see, for example, Courtis, Christian, “Luces and sombras. La exigibilidad de los derechos económicos, sociales y culturales en la sentencia de los “Cinco Pensionistas” de la Corte Interamericana de Derechos Humanos,” in Revista Mexicana de Derecho Público, No. 6, ITAM, Law Departament, Mexico, 2004. 103 Abramovich, Víctor, and Rossi, Julieta, “La tutela de los derechos económicos, sociales y culturales en el artículo 26 de la Convención Americana sobre Derechos Humanos”, Estudios Socios Jurídicos, Bogotá, Special No. 9, April 2007, pp. 46 and 47. 104 Ibidem, p. 48. 105 With certain variations, see Courtis, Christian, “La protección de los derechos económicos, sociales y culturales a través del artículo 26 de la Convención Americana sobre Derechos Humanos,” op. cit. supra note 79; and Melish, Tara J., “El litigio supranacional de los derechos económicos, sociales y culturales: avances y retrocesos en el Sistema Interamericano,” in Memorias del seminario internacional sobre derechos económicos, sociales y culturales, Mexico, Foreign Affairs Secretariat, pp. 173 to 219; by the same author, La Protección de los Derechos Económicos, Sociales y Culturales en el Sistema Interamericano de Derechos Humanos, op. cit. supra note 79. 21