Sunan an-Nasa'i, Volume 3, Book 24, Hadith 2678 (DarusSalam) ⓘ
It was narrated that Ibn 'Umar said: "A man came to the Prophet and said: 'What should we wear when we enter Ihram?' He said: 'Do not wear shirts, or 'Imamahs, or burnouses, or pants, or Khuffs unless there are no sandals; if there are no sandals, then wear Khuffs that come beneath the ankles. And (do not wear) any garment that has been dyed with Wars or saffron, or has been touched by Wars or saffron.
أَخْبَرَنَا أَبُو الأَشْعَثِ، أَحْمَدُ بْنُ الْمِقْدَامِ قَالَ حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، قَالَ حَدَّثَنَا ابْنُ عَوْنٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ نَادَى النَّبِيَّ صلى الله عليه وسلم رَجُلٌ فَقَالَ مَا نَلْبَسُ إِذَا أَحْرَمْنَا قَالَ " لاَ تَلْبَسِ الْقَمِيصَ وَلاَ الْعَمَائِمَ وَلاَ الْبَرَانِسَ وَلاَ السَّرَاوِيلاَتِ وَلاَ الْخِفَافَ إِلاَّ أَنْ لاَ يَكُونَ نِعَالٌ فَإِنْ لَمْ يَكُنْ نِعَالٌ فَخُفَّيْنِ دُونَ الْكَعْبَيْنِ وَلاَ ثَوْبًا مَصْبُوغًا بِوَرْسٍ أَوْ زَعْفَرَانٍ أَوْ مَسَّهُ وَرْسٌ أَوْ زَعْفَرَانٌ " .
also referenced under: Hadith 2677 (Reference) & Book 24, Hadith 0 (In-Book)