Who said "Motivation comes from believing you can do it."?

This quote is attributed to Barney.

Motivation comes from believing you can do it. - Barney

"Motivation comes from believing you can do it."

Barney Motivation

"I love you, you love me, we're a happy family"

"With a great big hug and a kiss from me to you, won't you say you love me too?"

"Friends forever, that's what we'll be"

"Everyone is special, everyone is unique"

"I believe in working hard for what you want."

"Never underestimate the power of determination."

"I don't need a reason to fight."

"The most important thing is the mission. Nothing else matters."