Council for Research in Values and Philosophy
crvp.orgCRVP publish a variety of books in a number of areas quite unrelated to Advaita. One book however (IIIB.4) covers the work of Shankara in considerable depth. It is 'Self Realisation (Brahmaanubhava): The Advaitic Perspective of Shankara: Indian Philosophical Studies IV' by Vensus A. George. It may be purchased but is also available for free download for personal study.