Phineas & Ferb Early Comic Reader #4 Its About Time

"A tricky time machine turns an ordinary day of summer vacation into a struggle for survival when Phineas, Ferb, and Candace end up in the Jurassic period! The kids must avoid being trampled by Tyrannosaurus rexes and find a way to make it back to their own time, before mom and dad find out! Meanwhile, Perry the Platypus discovers that Dr. Doofenshmirtz has a brand-new nemesis - Peter the Panda!"