Palestinian prisoners in Guinness Book of Records

According to the report, Palestinian prisoner Sa'id Al-Ataba has been detained for more than 30 years which is the longest imprisonment in the world. No other political prisoner had served such a long period ; Nelson Mandela had served 26 years, and Lee Harvey Oswald, the assassin of former US president John Kennedy served 28 years in prison.

Emphasis added.

Fun Fact: Lee Harvey Oswald was a homing pigeon enthusiast. News to me.