It is narrated from Sayyiduna Jubayr bin Mut'im (may Allah be pleased with him) that when the Prophet (peace and blessings be upon him) began the prayer, after saying the takbir he would say: "'Allahu akbaru kabiran, wa al-hamdu lillahi kathiran, wa subhana Allahi bukratan wa asila' (Allah is the Greatest, truly great; much praise be to Allah; and glory be to Allah morning and evening), saying each phrase three times, then: 'A'udhu billahi min al-shaytani al-rajim: min nafkhihi wa nafthihi wa hamzih' (I seek refuge with Allah Almighty from Satan the accursed, from his whisperings, from the wind of arrogance and from the hissing of magic)."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2353