سُنَنُ أَبِي دَاوُدَ
Sunan Abi Dawud 769
Prayer (Kitab Al-Salat)
The Supplication With Which The Prayer Should Be Started
حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، قَالَ لاَ بَأْسَ بِالدُّعَاءِ فِي الصَّلاَةِ فِي أَوَّلِهِ وَأَوْسَطِهِ وَفِي آخِرِهِ فِي الْفَرِيضَةِ وَغَيْرِهَا .
Malik said: There is no harm in uttering supplication in prayer, in its beginning, in its middle, and in the end, in obligatory prayer or other.
Sunan Abi Dawud, 769Sahih Maqtu' (Al-Albani)صحيح مقطوع (الألباني)