Dyfyniad APA

Hartmann, W. K., & William K. Hartmann; Chris Impey. Astronomy: The cosmic journey. Pacific Grove, CA: Brooks/Cole.

Dyfyniad Arddull Chicago

Hartmann, William K., và William K. Hartmann; Chris Impey. Astronomy: The Cosmic Journey. Pacific Grove, CA: Brooks/Cole.

Dyfyniad MLA

Hartmann, William K., và William K. Hartmann; Chris Impey. Astronomy: The Cosmic Journey. Pacific Grove, CA: Brooks/Cole.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.