It wasnarrated from Ibn 'Umar that the Prophet (ﷺ) used to put oilonhis head when he was in the state of Ihram, but not oil that wasperfumed. (ID)
English reference (ID): Vol. 4, Book 25, Hadith 3083 (ID)
Arabic reference (ID): Book 25, Hadith 3201 (ID)