Who said "The human spirit cannot be broken by chains or walls."?

This quote is attributed to Oliver Tambo.

The human spirit cannot be broken by chains or walls. - Oliver Tambo

"The human spirit cannot be broken by chains or walls."

Oliver Tambo Strength

Anti-apartheid Leader, Politician South African 1917–1993

"The struggle is my life. I will continue fighting for freedom until it is won."

"Unity is strength. Division is weakness."

"An ideal is not as ideal unless it is universal."

"We must never give up the fight for justice, no matter how long it takes."

"Strength comes from within."

"A woman should be proud of who she is."

"A strong woman can overcome anything."

"The only thing I'm good at is killing."