?????????? ??? ??????? ? ???????????? ? ??????????? ?? «???????????».Methyl blue could be the dominant blue pigment in inks Employed in pens.[31] Blueprinting includes the manufacture of Prussian blue in situ.? ??????? ? ????? ??????????? ????????? ???????? ?????? ? ??????? ? ??????????? ??????? ?? ???????????? ????????? ? ???????????? ??????????… Read More