[groff] Groff with refer and et-al

[Jaakko Pulkkinen]

I am having an issue with getting et-al to function properly.

I have the following bibliography entry:
%K atkinson2017
%A Susan Nolen-Hoeksema
%A Barbara L. Fredrikson
%A Geoffrey R. Loftus
%A Christel Lutz
%T Atkinson & Hilgard's Introduction to psychology
%I Andrew Ashwin
%D 2017

My groff settings:
.R1
database ../bibliography
et-al " et al." 1 2
bracket-label " (" ) "; "
label "(@.n|Q) ', ' (D.y|D)"
no-label-in-reference
accumulate
move-punctuation
.R2

Running refer and groff with:
$ refer hops.ms | groff -D utf-8 -ms -T pdf > hops.pdf

What I am getting is :
(Nolen-Hoeksema, 2017).

What I am expecting is:
(Nolen-Hoeksema et-al., 2017).

Any help would be appreciated!

Cheers!