A Dream of Wings, Crouch, T., 1981, p.148; The Capital, 1893-10-21, p.9

p. 148: "Washington gossips spread tales of Langley's imperious attitude. As one columnist noted, "It is well known that the professor 'has a way with him' of making his rolay personality felt in his big brownstone building." He was also accused of taking credit for other men's work. A few of his peculiarities, notably his unwillingness to allow a subordinate to precede him down a hall or up a flight of stairs, became matters of jest among the staff." 

p. 320 (footnote) The capital, 1893-10-21, p.9