In January 2016, it was discovered that there is a considerable overlap between:

J.M. Swart (2006): Duals and thinnings of some relatives of the contact
process (Prague Stochastics 2006, M. Hušková and M. Janžura (eds.),
Matfyzpress, Prague),

and

M. Hutzenthaler and R. Alkemper (2007): Graphical representation of some
duality relations in stochastic population models.
(Electron. Commun. Probab. 12, 206-220).

Both papers were written in good faith at roughly the same time, without one
(group of) author(s) being aware of the other. It is possible that the papers
are not fully independent in the sense that informal discussions between me
and Martin Hutzenthaler some years earlier may have influenced both of
us. Since this is some 10 years ago now, we do not remember exactly what we
discussed at the time.