d.

  BETA    (input) DOUBLE PRECISION
          The scalar beta. When beta is zero then C need not be set
          before entry.

  TC      (input)  DOUBLE PRECISION array, dimension (LDTC,L)
          On entry with LDBLK = 'C', the leading M*K-by-L part of
          this array must contain the first block column of T.
          On entry with LDBLK = 'R', the leading (M-1)*K-by-L part
          of this array must contain the 2nd to the M-th blocks of
          the first block column of T.

  LDTC    INTEG