A remark on off-diagonal long range order
  In this work, we study some general property of a strongly correlated electron system defined on a lattice. Assuming that the lattice system exhibits off-diagonal long range order, we show rigorously that this assumption would lead to Meissner effect. This generalizes previous results of continuous case to a lattice electron system. 
C. A. Piguet, D. F. Wang and C. Gruber