GRAPHS AND COMBINATORICS, vol.32, no.3, pp.903-912, 2016 (SCI-Expanded)
This work provides an orthogonal trade for all possible volumes N is an element of Z(+) \ {1, 2, 3, 4, 5, 7} for block size 4. All orthogonal trades of volume N <= 15 are classified up to isomorphism for this block size. The intersection problem for orthogonal arrays with block size 4 is solved for all but finitely many possible exceptions.