35J05 Laplacian operator, reduced wave equation (Helmholtz equation), Poisson equation [See also 31Axx, 31Bxx] 13945

35J86 Linear elliptic unilateral problems and linear elliptic variational inequalities [See also 35R35, 49J40] 116

35J87 Nonlinear elliptic unilateral problems and nonlinear elliptic variational inequalities [See also 35R35, 49J40] 292