Cookie and Kate's Amazon Page
The Flavor Bible: This reference book lists which flavors pair well with others, which is convenient when improvising with what's on hand. I don't know what I'd do without it!

Cookie and Kate
A flavor pairing color analogy
"Aroma similarity prediction (the 'flavor pairing hypothesis') is a tool to identify Z which (surprisingly) turns out to be quite similar to A because they share key odorants. As mentioned above, finding Z is what is difficult." Martin Lersch, A Flavor Pairing Color Analog