Localized superconductive pairs
  Different physical phenomena are discussed which should help to comprehend and interpret the concept of localized superconductive pairs; these include behavior of highly resistive granular materials with superconducting grains, parity effect and the Berezinskii--Kosterlitz--Thouless transition. Experimental arguments in support of localized pairs existence are presented and conditions which promote their appearance are analyzed. 
V. F. Gantmakher
cond-mat.supr-con