What was the last book published by dr seuss before his death?

"Oh, the places you will go! "

I babysit a lot :P that should be his last book before he died. It was published in 1990. And he died in 1991.

I hope this has helped you :) if so please help me by rating me the brainlest :) I am trying to level up and I only need 3 more :)
Please and thank you! ☺️

Oh the places you will go. By dctr seuss. You're welcome

Your answer is true : )