Vani Devi sings in a satsang the mantra or kirtan "Om Sat Chit Ananda" which you can find in the kirtan songbook as No. 562. Here is the text:
Om Sat Chit Ananda Parabrahma
Sri Bhagavathe Sametha
Sri Bhagavathe Namaha
Infos in German about yoga, meditation and ayurveda on our webpages at www.yoga-vidya.org - the complete kirtan songbook with Mp3-files and videos to sing along can be found in our German Yoga Community on Yoga Vidya Kirtan Songbook.