1 files changed, 5 insertions, 2 deletions
diff --git a/def.peg b/def.peg
index 8bec09d..336a446 100644
--- a/def.peg
+++ b/def.peg
@@ -11,17 +11,20 @@ Markdown       <- MetaBlock* Block*
 Block          <- Header / List / LinkDefinition / Paragraph
 Header         <- '#'+ SPACE* !NEWLINE Words? SPACE* NEWLINE
 List           <- ([-*]+ / [[:digit:]]+ [).]) (_ (List / Words))? NEWLINE
-LinkDefinition <- LinkLabel ':' _? Uri (_ '"' !'"' PlainWords '"')? NEWLINE
+LinkDefinition <- LinkLabel ':' _? Uri (_ LinkTitle)? NEWLINE
 Paragraph      <- Words (HardBreak Words)* NEWLINE+
 
 # Inline elements
 Words          <- StyledWords / LinkedWords / AnnotatedWords / PlainWords
 StyledWords    <- '*' Words '*' / '**' Words '**' / '_' Words '_'
-LinkedWords    <- '[' Words ']' '(' Uri ')'
+LinkedWords    <- '[' Words ']' '(' ((Uri _)? LinkTitle / Uri) ')'
                 / '[' Words ']' LinkLabel
                 / LinkLabel
 AnnotatedWords <- '[' Words ']' '{' ![{}] PlainWords '}'
 LinkLabel      <- '[' _? ![\[\]] PlainWords _? ']'
+LinkTitle      <- '"' _? !'"' _? PlainWords _? '"'
+                / "'" _? !"'" PlainWords _? "'"
+                / "(" _? ![()] PlainWords _? ")"
 PlainWords     <- PRINTABLES (_ PRINTABLES)*
 Uri            <- '<' ![<>] PRINTABLES? '>' / ![<>] PRINTABLES
 HardBreak      <- SPACE SPACE+ NEWLINE