It is narrated from Salamah bin Akwa’ (may Allah be pleased with him) who said: “I said, O Messenger of Allah (ﷺ), we are out hunting, can we pray in a single shirt?” He (ﷺ) said: “Yes, and sew it. If you cannot do that, then fasten it with a thorn.”
Hadith Referenceمسند الإمام الشافعي / كتاب الصلاة / 186
Hadith Takhrijأخرجہ ابو داود، الصلاۃ، باب الرجل یصلی فی قمیص واحد: 632 - والنسائی، القبلۃ، باب الصلوۃ فی قمیص واحد: 766 - وصححہ ابن خزیمہ: 777، 778 - والحاکم: 1/250۔