1. The Sources of Human Rights Law : Custom, Jus Cogens, and General Principles
2. Philosopher Henry Shue'sBasic Rights: Subsistence, Affluence and US Foreign Policy(1980) is commonly credited as having first conceptualised a multiple obligations structure applicable to all human rights. See 52 (duties to avoid, protect and aid). And see H Shue ‘The Interdependence of Duties’ in P Alston & K Tomasevski (eds)The Right to Food(1984) 83. International legal scholars and treaty body experts then began to work with the structure, initially in relation to rights in the ICESCR and increasingly in relation to all the core UN human rights treaties as it is recognised that no single right in any treaty is either ‘negative’ or ‘positive’ but generates a range of obligations, both negative and positive — obligations which are made concrete as interpretive practice and experience evolves. See, for example, GJH van Hoof ‘The Legal Nature of Economic, Social and Cultural Rights: A Rebuttal of Some Traditional Views' in Alston & Tomasevski 97; S Holmes & CR SunsteinThe Cost of Rights: Why Liberty Depends on Taxes(1999).