Book Reference for Pachyrrhynchus and allied

Emmanuel,
quite recently some new Pachyrhynchus species from Mindanao were described (and properly illustrated) by Hiraku Yositake, but no books or articles exist to satisfy your request. I am collecting and studying Pachyrhynchines for some years (a paper by me with the description of three new Pachyrhynchus species is in press), thus I know quite well the bibliographical situation: most, if not all, articles are dated before 1935, and are pure text with descriptions.
About the genus Doliops the situation is by far better, because there are some articles by Vives and Barsevskis who described and illustrated many new taxa.


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