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Foo [bar] [1].

Foo [bar][1].

Foo [bar]
[1].

[1]: /url/  "Title"


With [embedded [brackets]] [b].


Indented [once][].

Indented [twice][].

Indented [thrice][].

Indented [four][] times.

 [once]: /url

  [twice]: /url

   [thrice]: /url

    [four]: /url


[b]: /url/

More multi line edge cases. First a broken link id

[link 
text] [link
id]

[link id]: /someurl/

Then a line with 2 chars of trailing whitespace and a line break [my  
University][].

The a shortcut reference link with 2 chars of trailing whitespace and a line break [my  
University].

  [my university]: http://www.ua.es