Mastodonia
Science Fiction
Asa Steele was unprepared for the incredible events that began to unfold when Rila Elliot--a long-lost love--stepped out of the past and his faithful dog Bowser started loping into it through time trails he'd discovered in his own backyard.  Rila's appearance was mere coincidence, but Bowser's retrieval of fresh dinosaur bones was as inexplicable as was the curious crater in Asa's backyard that seemed to have been made by a spaceship from the stars.

Soon Asa himself tripped in time, led into prehistoric eras by an enigmatic cat-faced alien. In short order, the time trails in the quiet town of Willow Bend became the focus of global attention and government scrutiny. Then time-traveling turned into big business and led to big trouble, when Asa and Rila uncovered an interstellar mystery from before recorded time!

Also published titled "Catface"
Extraterrestrial beings, Time travel, Fiction, Science Fiction, aliens
Clifford D. Simak
Clifford Donald Simak (August 3, 1904 – April 25, 1988) was an American science fiction writer. He won three Hugo Awards and one Nebula Award.The Science Fiction Writers of America made him its third SFWA Grand Master,[4] and the Horror Writers Association made him one of three inaugural winners of the Bram Stoker Award for Lifetime Achievement.[5] He is associated with the pastoral science fiction subgenre.