"While the ages cannot yet be accepted unequivocally," the archeological team concluded, "neither can they be easily dismissed."

The Canadian Sandhill Crane is morphologically not reliably distinct and was never unequivocally accepted as valid subspecies.

Although this move was never unequivocally accepted, it was the dominant treatment throughout most of the 20th century.

There are only 3 unequivocally accepted extant genera of Piesmatidae:

There are a number of closely related taxa which hybridize with L. galeobdolon and in some cases are not unequivocally accepted as distinct species but considered subspecies or varieties by many authors.

Granting that the Beowulf reference, though tantalisingly close to unambiguity, cannot be unequivocally accepted as a primary source for Hercule Poirot, the directness of the next reference brooks no denial.

Some Paleogene fossils are not unequivocally accepted to be of psittaciforms:

Three genera are unequivocally accepted to belong to the Presbyornithidae:

If that concept were unequivocally accepted, the ideas put forward by Leo Tindemans would have greater chance of success.

Two subspecies are unequivocally accepted (Snow et al. 1998), but they are increasingly considered separate species (Helbig 2001, Jønsson & Fjeldså 2006):