It should be noted that the Siegwarth et al. paper was never actually published as a third volume of Hunteria was never produced, and whichever 77 page version was intended for publication has not been made public. The linked version (which dates from at least 1996 based on its bibliography) should actually be cited as-
Siegwarth, Lindbeck, Redman, Southwell and Bakker, unpublished.
Megalosaurid dinosaurs from the Late Jurassic Morrison Formation of eastern Wyoming. 79 pp.
There's also an earlier version of the manuscript (which dates from at least 1994) that was circulated online-
Siegwarth, Lindbeck, Redman, Southwell, unpublished. Giant carnivorous
dinosaurs of the family Megalosauridae from the Late Jurassic Morrison
Formation of eastern Wyoming. Contributions from the Tate Museum
Collections, Casper, Wyoming. 2, 40 pp.
But this time, that journal doesn't exist, so the citation of it being in a Volume 2 is fictitious.
Mickey Mortimer