Singly-even self-dual codes with minimal shadow
  In this note we investigate extremal singly-even self-dual codes with minimal shadow. For particular parameters we prove non-existence of such codes. By a result of Rains \cite{Rains-asymptotic}, the length of extremal singly-even self-dual codes is bounded. We give explicit bounds in case the shadow is minimal. 
Stefka Bouyuklieva and Wolfgang Willems
math.CO cs.IT math.IT