[Advaita-l] Reference check.

[v.sh]

Namaskars. 

I am trying to track the original source in Vedas/Upanishads/Bhashyas of the
following prayer for a project we are doing:
            Sarve Bhavantu Sukhinah
            Sarve Santu Niramayaah
            Sarve Bhadrani Pashyantu
            Maa Kaschit Duhkhabhahg Bhavet

Could the erudite members of the list help me locate it?

Thanks in advance for your help.

Venkat Shrinivas
http://philosophyfoundation.blogspot.com/