North, G. (1997). Advanced amateur astronomy (2nd ed.). Cambridge University Press.
Chicago-stil citatNorth, Gerald. Advanced Amateur Astronomy. 2nd ed. Cambridge: Cambridge University Press, 1997.
MLA-referensNorth, Gerald. Advanced Amateur Astronomy. 2nd ed. Cambridge University Press, 1997.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.