On linear MDS codes of length $q+1$ over GF(q) for even q. (English)
J. Comb. Theory, Ser. A 49, No.1, 172-174 (1988).
Summary: Monomial matrices are constructed which transform doubly-extended Reed- Solomon codes into BCH codes of length $q+1$ over GF(q), where q is a power of 2.