Delocalization of the six electrons of cyclopropane's three C-C σ bonds was given as an explanation of the only slightly greater strain of cyclopropane ("only" 27.6 kcal/mol) as compared to cyclobutane (26.2 kcal/mol) with cyclohexane as reference with Estr=0 kcal/mol. This stabilization is referred to as σ aromaticity, in contrast to the usual π aromaticity, that, for example, is a highly stabilizing effect in benzene. Other studies do not support the role of σ-aromaticity in cyclopropane and the existence of an induced ring current; such studies provide an alternative explanation for the energetic stabilization and abnormal magnetic behaviour of cyclopropane.