or (b)." The schedule, in turn, lists the following documents. Most were British North America Acts and were renamed as Constitution Acts in 1982. Others include the Parliament of Canada Act, 1875, the Statute of Westminster, 1931, and acts that created new provinces or changed provincial borders. All of these acts were originally enshrined by the Colonial Laws Validity Act 1865 in the case of acts by the United Kingdom Parliament or enshrined by the British North America (No. 2) Act, 1949 or the British North America Act, 1871 in the case of acts by the Canadian Parliament. In addition to the acts listed here, six other acts were listed as constitutional in §52(2) but were repealed at the same time (see "Repealed constitutional documents", below). Amendments Part V of the Constitution Act, 1982 describes the process required for amending any constitutional document from then on. The general process requires the agreement of the federal government plus seven provinces with at least 50% of the population (section 38), but some amendments require unanimity of the provinces (section 41), and some can be done unilaterally by the federal government (section 44) or bilaterally by the federal government and a provincial government (section 43). As of 2013, eleven amendments have been made under the 1982 amending formula, one of which was later repealed. Documents entrenched by reference A document can become entrenched in the Constitution if it is mentioned by a document that is already entrenched. There is no conclusive list of documents, or parts of documents, that are entrenched in this way, so courts may expand or restrict this list in the future. One notable example are agreements with the Aboriginal people of Canada. Section 35(1) of the Constitution Act, 1982 says that "the existing aboriginal and treaty rights of the aboriginal peoples of Canada are hereby recognized and affirmed", while section 25 recognizes that rights in the Charter will not abrogate or derogate from existing or future aboriginal rights. By referencing these agreements in a constitution act, these agreements are, themselves, given constitution-level authority. These rights include: Royal Proclamation of 1763 (7 October 1763 (UK), reprinted in RSC 1985, App II, No 1); and existing or future land claim agreements Some documents became entrenched in the constitution in 1982 because the amending formula in Part V of the Constitution Act, 1982, says that their subject matter can only be amended