A wonderful new book on the coinage of Trajan, including a marvelous catalogue publishing an immense number of new variants and illustrating every bust variety, was published by Bernhard Woyteck in 2010, Die Reichsprägung des Kaisers Traian (98-117).
Jbhamon's coin in Woytek's catalogue: 580t, 7 specimens known to him, including BM 639 corr. In contrast Woytek knew the commonest bust type with this reverse in 88 specimens.
Iovi's coin: Woytek 562h, six spec. known to him, including Paris 875.