Provenance ownership, and of evidence left in books that shows how readers interacted with them. Provenance studies may shed light on the books themselves, providing evidence of the role particular titles have played in social, intellectual and literary history. Such studies may also add to our knowledge of particular owners of books. For instance, looking at the books owned by a writer may help to show which works influenced him or her. Many provenance studies are historically focused, and concentrated on books owned by writers, politicians and public figures. The recent ownership of books is studied, however, as is evidence of
International Convention Relating to Intervention on the High Seas in Cases of Oil Pollution Casualties 1969 entering into force in 1975. In 1973 the Protocol relating to Intervention on the High Seas in Cases of Marine Pollution by Substances other than Oil was adopted extending the provision of the 1969 Convention to other hazardous substances. The list of hazardous substances covered by Protocol was amended and extended in 1991, 1996 and 2002. As of October 2016, the convention has 89 state parties. The Convention applies to all seagoing vessels except warships or other vessels owned or operated by a State and used on Government non-commercial service. While exercising the right to take measures "necessary to