added comments

drkameleon · Sep 9, 2024 · 28a32a8 · 28a32a8
1 parent 0c18140
commit 28a32a8
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/src/plugins/isbn.art b/src/plugins/isbn.art
@@ -31,6 +31,7 @@ action: function [str, params][
  ] -> return false
 
  isIsbn10?: function [isbn][
+ ; see: https://en.wikipedia.org/wiki/ISBN#ISBN-10_check_digit_calculation
  if 10 <> size isbn -> return false
  [s, t]: 0
  loop 0..9 'i [
@@ -41,6 +42,7 @@ action: function [str, params][
  ]
 
  isIsbn13?: function [isbn][
+ ; see: https://rosettacode.org/wiki/ISBN13_check_digit#Arturo
  if 13 <> size isbn -> return false
  s: 0
  loop.with:'i isbn 'n [