The 1971 Thompson and Acosta personae , on which Raoul Duke and Dr. Gonzo were basedThompson wrote that he concluded their March trip by spending some thirty-six hours alone in a hotel room `` feverishly writing in my notebook '' about his experiences . Thompson wrote that he concluded their March trip by spending some thirty-six hours alone in a hotel room `` feverishly writing in my notebook '' about his experiences .