Tilaka

Padma Purana states:

vama-parshve sthito brahma dakshine cha sadashivaha madhye vishnum vijaniyat Tasman madhyam na lepayet 

1. On the left side of the tilaka Lord Brahma is situated, 
2. On the right side is Sadashiva, 
3. In the middle dwells Lord Vishnu. 

https://en.wikipedia.org/wiki/Tilaka

De
http://www.harekrsna.de/Tilak.htm

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http://www.stephen-knapp.com/tilak_why_wear_it.htm

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http://www.bhagavadgitausa.com/TILAKAM.htm

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http://xa.yimg.com/kq/groups/21892404/1152816336/name/Types%20of%20Tilak.ppt

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