I just came across the following new publication. SpringerBriefs in Mathematics. (Somewhere between a paper and a book; 50-125.) I think It is not what was originally asked for, but might be close to some things that came up in the discussion.
Since it is new, and I only know what is written on the webpage, the relevance of this to the subject at hand is not yet completely clear to me. Still, I hope it is close enough to be on-topic. [Some of the text below is the same for all Briefs in different fields, which might explain some possibly surprising formulations.]
From http://www.springer.com/series/10030https://www.springer.com/series/10030
Excerpts from the page.
SpringerBriefs present concise summaries of cutting-edge research and practical applications across a wide spectrum of fields. Featuring compact volumes of 50 to 125 pages, the series covers a range of content from professional to academic. [...]
Typical topics might include:
.) A timely report of state-of-the art techniques .) A bridge between new research results, as published in journal articles, and a contextual literature review .) A snapshot of a hot or emerging topic .) An in-depth case study .) A presentation of core concepts that students must understand in order to make independent contributions
SpringerBriefs in Mathematics showcase expositions in all areas of mathematics and applied mathematics. Manuscripts presenting new results or a single new result in a classical field, new field, or an emerging topic, applications, or bridges between new results and already published works, are encouraged. The series is intended for mathematicians, applied mathematicians.
