Imlay, R. W. (1982). Jurassic (Oxfordian and Late Callovian) ammonites from the western interior region of the United States: Marine waters invaded Montana in late Callovian time, advanced southward across Wyoming in early Oxfordian time and persisted in Montana during late Oxfordian time. United States Gov. Print. Off.
Chicago-Zitierstil (17. Ausg.)Imlay, Ralph Willard. Jurassic (Oxfordian and Late Callovian) Ammonites from the Western Interior Region of the United States: Marine Waters Invaded Montana in Late Callovian Time, Advanced Southward Across Wyoming in Early Oxfordian Time and Persisted in Montana During Late Oxfordian Time. Washington: United States Gov. Print. Off, 1982.
MLA-Zitierstil (9. Ausg.)Imlay, Ralph Willard. Jurassic (Oxfordian and Late Callovian) Ammonites from the Western Interior Region of the United States: Marine Waters Invaded Montana in Late Callovian Time, Advanced Southward Across Wyoming in Early Oxfordian Time and Persisted in Montana During Late Oxfordian Time. United States Gov. Print. Off, 1982.