On non-singular crack fields in Helmholtz type enriched elasticity   theories
  Recently, simple non-singular stress fields of cracks of mode I and mode III have been published by Aifantis (2009,2012), Isaksson and H\"agglund (2013) and Isaksson et al. (2012). In this work we investigate the physical meaning and interpretation of those solutions and if they satisfy important physical conditions (equilibrium, boundary and compatibility conditions). 
Markus Lazar, Demosthenes Polyzos
cond-mat.mtrl-sci physics.class-ph