I read an interview about this story but I didn t read the story, thanks
(gotta find this interview)
found it , sorry, it' s in french : http://www.editions-delcourt.fr/aller_plus_loin/dossiers_bd/mike_mignola_presente_l_homme_a_la_tete_de_vis_et_autres_histoires_dejantees
and by the way, I found in a small edition (wetta), an aliens comics by mignola and dave gibbons (watchmen) ! I couldn t buy it now but it looks cooool .
and there is also in the same edition a comics of "the keep" with a "preface" from the novel' s author .