[3] Adobe Type 1 Font Format - T1_SPEC.pdf, , https://adobe-type-tools.github.io/font-tech-notes/pdfs/T1_SPEC.pdf
[4] Type 1 Font Format Supplement - 5015.Type1_Supp.pdf, , https://adobe-type-tools.github.io/font-tech-notes/pdfs/5015.Type1_Supp.pdf
[1] tn5049: The StemSnap Hint Operator for Type 1 Font Programs - 5049.StemSnap.pdf, , https://adobe-type-tools.github.io/font-tech-notes/pdfs/5049.StemSnap.pdf
[2] Designing Multiple Master Typefaces - 5091.Design_MM_Fonts.pdf, , https://adobe-type-tools.github.io/font-tech-notes/pdfs/5091.Design_MM_Fonts.pdf