Peru
noun: Peruvian(s)
adjective: Peruvian
Philippines
noun: Filipino(s)
adjective: Philippine
Pitcairn Islands
noun: Pitcairn Islander(s)
adjective: Pitcairn Islander
Poland
noun: Pole(s)
adjective: Polish
Portugal
noun: Portuguese (singular and plural)
adjective: Portuguese
Puerto Rico
noun: Puerto Rican(s) (US citizens)
adjective: Puerto Rican
Qatar
noun: Qatari(s)
adjective: Qatari
Reunion
noun: Reunionese (singular and plural)
adjective: Reunionese
Romania
noun: Romanian(s)
adjective: Romanian
Russia
noun: Russian(s)
adjective: Russian