Heck, A., & Perdang, J. (1991). Applying fractals in astronomy. Springer-Verlag.
Chicago Style aipamenaHeck, A., and J.M Perdang. Applying Fractals in Astronomy. New York: Springer-Verlag, 1991.
MLA aipamenaHeck, A., and J.M Perdang. Applying Fractals in Astronomy. Springer-Verlag, 1991.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.