Hi Chris, I still have problems figuring out the equation symbolism. In the example below, once appear [ {d a} , {d a} ], and next is [ {js} , {a} ] . What is the idea behind this notation ? Thank you, Marius B. Equation { Galerkin { [ nu[] * Dof{d a} , {d a} ] ; In Domain_Mag ; Jacobian Vol ; Integration CurlCurl ; } Galerkin { [ - Dof{js} , {a} ] ; In DomainS_Mag ; Jacobian Vol ; Integration CurlCurl ; } }