The CIBF has had problems in recent years . Leftist and Muslim militant authors , works critical of the government , and works with sections or topics that are seen as sexually or culturally controversial have been banned from the book fair . The CIBF has been marred in recent years by charges that leftist and Muslim militant authors , works critical of the government , and works featuring passages or topics deemed sexually or culturally controversial have been banned from presentation at the book fair .