Charlin also mentioned (with photo) in this paper on history of binaural (first PDF below, page 772).
A current and frequent user of the Jeckilin is ex-Decca engineer, Simon Eadon. Shown are a couple of his sessions.
Many years later, Jecklin inceased the dimensions and spacing for less 'mono-ish' sound at low frequencies (see JecklinDisk PDF).
Jecklin (and baffled, head-spaced omni techniques in general) works best on smaller enembles and/or those without a lot of LF content (small to medium size choirs, and chamber groups). For full orchestra they are best combined with widely spaced omni 'outriggers', or 'flanks'.
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It's worth mentioning that Alan Blumlein described the technique of head-spaced baffled omnis in the '30s! (long before Jecklin or Charlin). Best known for the technique of figure-8s coincident at 90 degrees, he was also the first to describe baffled omnis.