I don't know the answer to this. But I suspect that that the source was from one of the collection of fonts associated with the STIX project research that led to the collection of mathematical symbols additions noted in L2/01-067 (superseded by L2/01-142), as well as the earlier mathematical symbols proposals with the bulk of the symbols that were added to Unicode 3.2.
Given that context, it is, indeed, most likely that the symbols were associated with some publication(s) in game theory, rather than with professional Go notations per se. See, for example, Mathematical Go: Chilling Gets the Last Point: http://www.amazon.com/Mathematical-Go-Chilling-Gets-Point/dp/1568810326 I don't see black/white circles with dots in the bit of that publication scanned on Amazon, but it does use a black circle with a delta symbol as part of the game notation for discussion, as well as black and white circles with numbers, denoting sequences of stone placements. But to know for sure, you would probably have to get confirmation of original sources from Barbara Beeton and/or Patrick Ion, who collected together symbol candidates from a multitude of print sources back in the 1998 - 2001 time frame. --Ken On 3/9/2016 1:17 PM, Ori Avtalion wrote:
Unicode includes the following symbols as "Go Markers": * U+2686 ⚆ WHITE CIRCLE WITH DOT RIGHT * U+2687 ⚇ WHITE CIRCLE WITH TWO DOTS * U+2688 ⚈ BLACK CIRCLE WITH WHITE DOT RIGHT * U+2689 ⚉ BLACK CIRCLE WITH TWO WHITE DOTS It is unclear what they are for. I hope someone could explain. 1) I could not find any Go notation that uses dots inside the stones. 2) Why are there no symbols for white/black stones without dots? 3) An earlier proposal [1] suggested additional symbols: * GRAY CIRCLE WITH GRAY DOT RIGHT * GRAY CIRCLE WITH GRAY TWO DOTS * GRAY FILLED CIRCLE WITH WHITE DOT RIGHT * GRAY FILLED CIRCLE WITH WHITE TWO DOTS what was their purpose? Any why are Go Markers proposed as "Mathematical symbols"? Are they meant for mathematical research of the game of Go and not for actual notation? [1] http://www.unicode.org/L2/L2001/01067-n2318-mathadd4.pdf Thanks in advance!