This may be the link you have in mind: http://public.oed.com/how-to-use-the-oed/abbreviations/. It's a list of abbreviations used in the OED, including 'unkn.' meaning 'unknown'.The British abbreviation for "unknown" is "unkn." Rules disallow my providing a corroborating link so please google some combo of these words: public oed abbreviations.
Exactly. Thanks, EStjarn. When I tried to include it, I thought I got a moderator message that to avoid spam I must not include links. But I see that you have tenure. I shall work on my publications to gain some cachet. Thanks again. Users here will benefit from using this OED site.This may be the link you have in mind: [the link you provided; moderator banned my repeating it]. It's a list of abbreviations used in the OED, including 'unkn.' meaning 'unknown'.