[1] Up to this point the entry = Photius, Lexicon epsilon2000, and is similar to entries for e)skh/nwsen in Hesychius epsilon6232, Lexica Segueriana 237.10 and (according to Adler) the unedited Ambrosian Lexicon (2183). This conjunction between entries in various lexica, as well as the information imparted in the rest of the entry, reflects the fact that denominative derivatives of skhnh/ ('tent') occur as e-contracts, a-contracts and o-contracts. Of these, the o-contract forms are the most common. The particular form of the headword is attested outside lexicography only in five passages of Xenophon, where it usually refers to military encampment (though not always in tents: Anabasis 4.2.22 (web address 1)).
[2] From the scholia to Aristophanes, Acharnians 69 (web address 2), where the e- or a-contract form e)skhnhme/noi appears. The scholiast goes on to deny explicitly that the verb follows the third (o-contract) conjugation.
[3] The lexicographer asserts that the perfect middle form of the e- or a-contract (cf. under kappa 1483) is sometimes used where (he says) the equivalent o-contract form would be more appropriate, in the sense of "inhabit" a place, not necessarily in tents.