From d8080db7f7213b7afa8bd87952771dfe1d3f89ec Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Fri, 13 Nov 2015 11:00:56 -0800
Subject: [PATCH] Allow `://` in citation keys.

Closes jgm/pandoc-citeproc#166.
---
 src/Text/Pandoc/Parsing.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Text/Pandoc/Parsing.hs b/src/Text/Pandoc/Parsing.hs
index c64860ad9e11..02d114e0ffeb 100644
--- a/src/Text/Pandoc/Parsing.hs
+++ b/src/Text/Pandoc/Parsing.hs
@@ -1211,7 +1211,8 @@ citeKey = try $ do
   firstChar <- alphaNum <|> char '_' <|> char '*' -- @* for wildcard in nocite
   let regchar = satisfy (\c -> isAlphaNum c || c == '_')
   let internal p = try $ p <* lookAhead regchar
-  rest <- many $ regchar <|> internal (oneOf ":.#$%&-+?<>~/")
+  rest <- many $ regchar <|> internal (oneOf ":.#$%&-+?<>~/") <|>
+                 (oneOf ":/" <* lookAhead (char '/'))
   let key = firstChar:rest
   return (suppress_author, key)