Pseudodifferential Operators on Stratified Manifolds
  We consider a specific class of manifolds with singularities, namely, stratified manifolds, and describe a class of pseudodifferential operators (PsiDO) related to differential operators with degeneration of first-order with respect to the distance to the strata on such manifolds. (For manifolds with isolated singularities, this is a Fuchs type degeneration.) We restrict ourselves to the case of zero-order operators in L^2 spaces. The definition of PsiDO adopted in our approach uses induction over the number of strata in the manifold. The induction process naturally involves PsiDO with parameters. 
V. Nazaikinskii, A. Savin, B. Sternin