(a) Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates from the Prophet (peace and blessings be upon him) that he (peace and blessings be upon him) said: "The best of your clothes are the white ones, so let the living wear them, and shroud your dead in them."
(b) It is narrated from Abdullah bin Uthman bin Khuthaym similar to the previous hadith, but with different wording: "Wear white clothes, for they are the best of your clothes."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8951