Ashley Lister has his exercise up. He posts at the ERWA blog on the sixth of each month. This month he introduces the Kyrielle. I’d also add that the only additional commentary from Turco’s The Book of Forms (University Press of New England, Hanover & London, Third Edition, 2000, pp. 197-198)
is a French normative syllabic poem form written in quatrains. All lines are octosyllabic (in English meters, tetrameter)…
is that reference to tetrameter. Longman Dictionary of Poetic Terms doesn’t have the form, neither does Bob’s Byway, Poets.org, etc. This article out of Arizona State University expands even further than Lister’s article with a reference to the Encyclopedia Britannica. More importantly, I think, it specifically notes the use of quatrains which both Lister and Turco show in their rhyme scheme, but don’t specifically spell out. It also goes into greater detail about the refrain:
characterized by a refrain that is sometimes a single word and sometimes the full second line of the couplet or the full fourth line of the quatrain. (Encyclopedia Britannica)
Enough with quoting today, time to go write.