Não informado. Miscellaneous map series. Minnesota Geological Survey.
Lua i Stíl Chicago (17ú heag.)Não informado. Miscellaneous Map Series. Saint Paul, Minn: Minnesota Geological Survey.
Lua MLA (8ú heag.)Não informado. Miscellaneous Map Series. Minnesota Geological Survey.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.