Please sign a petition calling for more information about the father of the Booker-shortlisted writer, Hisham Matar. Jaballa Matar, a prominent Libyan political activist, was abducted from his home 20 years ago. JM Coetzee, Ian McEwan, Wole Soyinka and Margaret Atwood are among the distinguished writers who signed a letter to the UK government in support of Hisham's campaign.