i didn't use any ref for this one. the only thing i was having was this photo of a piece of glass i had found online, probably coming from an industrial constructor showing a sample of their glass stuff for marketing reasons. i found the tones fascinating and got inspired. i guess the whole thing made sense at a particular moment. :)
on the technical side, i have been painting a lot with the smudge tool lately, thanks to mister Thom Scholes himself. The smudge tool can allow a great control of your shapes via displacement of entire pannels and areas of your canvas. it's fascinating.