Boxer in book about African country (7)
I believe the answer is:
somalia
'african country' is the definition.
(Somalia is an example)
'boxer in book about' is the wordplay.
'boxer' becomes 'ali' (Muhammad Ali).
'in' indicates putting letters inside.
'book' becomes 'amos' (Old Testament book**).
'about' is a reversal indicator.
'amos' in reverse letter order is 'soma'.
'ali' going into 'soma' is 'SOMALIA'.
(Other definitions for somalia that I've seen before include "Mogadishu its capital" , "Land" , "Is Alamo an African state?" , "E. African state" , "Eastern African state" .)