Well,
here's a book that might work. And
this is the data sheet for the PIC 18F8520.
Also, try searching under Asm or Assembler if you haven't already, some people shorten it as those.
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2005 Las Vegas Regional Autodesk Visualization Award
2005 Las Vegas Regional #8 Seeded Alliance with 988 and 1505
2006 Southern California Regional #15 seed