Javier Felipe Ricardo Pérez de Cuéllar y de la Guerra KCMG ( born January 19 , 1920 ) is a Peruvian diplomat who served as the fifth Secretary-General of the United Nations from January 1 , 1982 to December 31 , 1991 .
Javier Pérez de Cuéllar Guerra ( born January 19 , 1920 ) is a Peruvian diplomat who served as the fifth Secretary-General of the United Nations from January 1 , 1982 to December 31 , 1991 .