[isurl]: someurl.html
 [1]:     otherurl.html

simple [URL][1] and [URL][isurl]

simple [URL] [1] and [URL]
[isurl]

simple [1][] and [isurl][]

simple [1] and [isurl]

this is [a holy [isurl]]

no [resolution][] here and [here]

with a [break 	 in
the text]

  [break in the text]: url.html

this not \[isurl] and not [isurl\]

a [Link with_BIG] letters

   [link WITH_big]: letters.html
                    'This is the title'

bad [no URL] d [isurl]

[no url] invalid.html
[no url]:

[URL but no title]: invalid.html

   "title"

test [url but no title]
test [urldef]

[urldef]: some.url 'title"


some [with spaces]

[with spaces]: with spaces.html "title"

this [is a 'special' occasion for /all/ of us]

[is a 'special' occasion for /all/ of us]: occasion.html


this is [predefined] for [URI]