Regular Hadamard matrices constructed from Hadamard 2-designs and conference graphs

Suppose there exists a Hadamard 2-$(m,\frac{m?1}{2},\frac{m?3}{4})$ design having skew incidence matrix. If there exists a conference graph on $2m?1$ vertices, then there exists a regular Hadamard matrix of order $4m^2$. A conference graph on $2m+3$ vertices yields a regular Hadamard matrix of order $4{(m+1)}^2$.