J.W.T. Youngs

Solution of the heawood map-coloring problem—Cases 3, 5, 6, and 9

J.W.T. Youngs, 1970 .

Solution of the heawood map-coloring problem—Case 2

Gerhard Ringel, J.W.T. Youngs, 1969 .

Solution of the heawood map-coloring problem—Case 4

L. R. Welch, J.W.T. Youngs, C. M. Terry, 1970 .

The symmetrization of matrices by diagonal matrices

Seymour V. Parter, J.W.T. Youngs, 1962 .

Solution of the Heawood map-coloring problem—case 11

Gerhard Ringel, G. Ringel, J. Youngs, 1969 .

Solution of the heawood map-coloring problem—Case 8

Gerhard Ringel, J.W.T. Youngs, 1969 .