I hope to take the time someday to actually add sources. Most of what I have here has been collected from hundreds of papers and books I've had to sift through. I am also not relatively certain about some things here. A temporal chart like the ones by Luke Ranieri might be an awesome project. Until then, enjoy!

и /i/ | ꙕ /y/ ꙑ /ɨ/ ѹ /u/
ь /ɪ/ ъ /ʊ/
е /ɛ/, ѧ /ẽ/ | ѭ /œ̃/ о /ʌ/, ѫ /ɔ̃/
ѣ /æ/ а /ɑ/