Shama-il Tirmidhi Chapter 053, Hadith Number 009 (376).

'Aayeshah Radiyallahu 'Anha said: "Rasulullah Sallalllahu 'Alayhi Wasallam passed away on a Monday".

Commentary
This has been mentioned previously. The muhadditheen and historians are unanimous in that Sayyidina Rasulullah Sallallahu 'Alayhi Wasallam passed away on Monday.