Drach, S. M., II, [317].

Drayson, G. A. W., II, [132], [132].

Dryden, II, [71].

Dual arithmetic, II, [186].

Duchesne, I, 52.

Dumortier, I, 313.

Duncan, A., I, 179.

Dunkin, E., II, [349].

Duodecimal scale, II, [68].

Duplication Problem, I, 349.