Who said "Time is the one enemy that cannot be defeated."?

This quote is attributed to Rhaegar Targaryen.

Time is the one enemy that cannot be defeated. - Rhaegar Targaryen

"Time is the one enemy that cannot be defeated."

Rhaegar Targaryen Time

"The dragon has three heads."

"I have a duty to my realm and to the future."

"Music is the voice of the soul."

"Love is the most powerful force in the world."

"Time waits for no one."

"Time spent with loved ones is never wasted."

"I've been alive for a long time. Long enough to know that you can't trust anyone."

"The past always catches up with you."