What has the author Charles Portis written?

Charles Portis has written:
'Gringos' -- subject(s): Fiction, Americans
'True Grit' -- subject(s): Fiction, Death, Teenage girls, United States marshals, Fathers, Revenge, Outlaws, Fiction in English
'Escape velocity' -- subject(s): Appreciation
'Gringos' -- subject(s): Americans, Fiction
'Norwood' -- subject(s): Fiction, Young men