From Ryuji Suzuki's web site, now apparently unavailable, the following from his article on paper developers:
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In DS-14, Dimezone S may be substituted with Dimezone, Phenidone B, or Phenidone in decreasing order of desirability. However, preparation of concentrate may face solubility challange with Dimezone or Phenidone B. Phenidone or Phenidone A provides equal image quality, but with inferior solution keeping property. One work-around is to prepare the concentrate with any of these Phenidone derivatives, and add Phenidone or Dimezone immediately before use.
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