Canada. Division of Seismology and Geomagnetism. http://id.loc.gov/authorities/names/no2016080038
Title:
Magnetic declination chart 1985.0, Canada : lines of equal magnetic declination (variation) and annual change = Carte déclinaison magnétique 1985.0, Canada : lignes d'égale déclinaison magnétique et variation annuelle / map produced by the Division of Seismology and Geomagnetism, Earth Physics Branch.
This resource is supported by the Institute of Museum and Library Services under the provisions of the Library Services and Technology Act as administered by State Library of Iowa.