# Operator splitting for 4 subproblems

Typically an ODE System which involves 2 different physical problems such as diffusion and advection can be numerically approached by the well known Strang operator splitting scheme. I'm wondering if there's a generalization of this scheme to an arbitrary number of subproblems.

In my case, there's an additional issue: I got 4 subproblems, two of which have a smaller time-scale (Maxwell equations with time-varying medium) than the remaining 2 (advection/diffusion). Any ideas, keywords, hints?