(17) باب بَيَانِ وُجُوهِ الإِحْرَامِ وَأَنَّهُ يَجُوزُ إِفْرَادُ الْحَجِّ وَالتَّمَتُّعِ وَالْقِرَانِ وَجَوَازِ إِدْخَالِ الْحَجِّ عَلَى الْعُمْرَةِ وَمَتَى يَحِلُّ الْقَارِنُ مِنْ نُسُكِهِ
A'isha (Allah be pleased with her) said:
Some among us put on Ihram for Hajj alone (Hajj Mufrad) ; some of us for Hajj and Umra together (Qiran), and some of us for Tamattal (first for Umra and after completing it for Hajj).
Reference: Sahih Muslim 1211 n
In-book reference: Book 15, Hadith 132
USC-MSA web (English) reference(deprecated numbering scheme): Book 7, Hadith 2777