Add the advisory opinion's code

Warning²Federal courts, Illinois courts21st and 22nd editions

An Inter-American Court advisory opinion is cited by the Court's words for the kind of opinion and the Court's own code; with many opinions issued, the code tells one from another.¹

1. 1R. 21.5.5(a) Advisory Opinions; R. 21.5.5 Inter-American Court of Human Rights. Tables: T3.7 Inter-American Court of Human Rights.
2. 2A warning: the form is usually wrong under the rule in note 1, and context can justify it.