Listen to Opening Invocation (Shlokas) online. Opening Invocation (Shlokas) is a Bengali language song and is sung by Suresh Wadkar and Sadhana Sargam. Opening Invocation (Shlokas), from the album Essential Chants Of Shiva, was released in the year 1991. The duration of the song is 2:20. Download Bengali songs online from JioSaavn.