Restored Leonardo Masterpiece on Display at the National Gallery in London (last par) The restoration process has provided the opportunity for a comprehensive study of 'The Virgin of the Rocks' by the National Gallery's Scientific, Conservation and Curatorial departments, with the findings being published online in the National Gallery's Technical Bulletin in September 2011. The Gallery will expand its initial research on Leonardo himself to include the systematic investigation of Leonardo's Milanese pupils, collaborators and followers.