Nested Multi-Soliton Solutions with Arbitrary Hopf Index
  Generalized Aratyn-Ferreira-Zimerman O(3) nonlinear sigma model with a particular symmetry breaking term, so-called dielectric function, is discussed. Static multi-soliton configurations with finite energy and nontrivial Hopf index are found. We show that such configurations consist of nested toroidal solitons. Moreover, nontrivial sphaleron-like solutions i.e. configurations with zero total topological charge are also presented. 
A. Wereszczynski