11.2 \footnotemark

Synopsis, one of:


Put the current footnote mark in the text. To specify associated text for the footnote see \footnotetext. The optional argument number causes the command to use that number to determine the footnote mark. This command can be used in inner paragraph mode (see Modes).

If you use \footnotemark without the optional argument then it increments the footnote counter, but if you use the optional number then it does not. The next example produces several consecutive footnote markers referring to the same footnote.

The first theorem\footnote{Due to Gauss.} 
and the second theorem\footnotemark[\value{footnote}] 
and the third theorem.\footnotemark[\value{footnote}]

If there are intervening footnotes then you must remember the value of the number of the common mark. This example gives the same institutional affiliation to both the first and third authors (\thanks is a version of \footnote), by explicitly specifying the number of the footnote (‘1’).

\title{A Treatise on the Binomial Theorem}
\author{J Moriarty\thanks{University of Leeds} 
  \and A C Doyle\thanks{Durham University} 
  \and S Holmes\footnotemark[1]}

This example accomplishes the same by using the package cleveref.

\usepackage{cleveref}[2012/02/15]   % in preamble 
The theorem is from Evers.\footnote{\label{fn:TE}Tinker, Evers, 1994.}
The corollary is from Chance.\footnote{Evers, Chance, 1990.}
But the key lemma is from Tinker.\cref{fn:TE}

It will work with the package hyperref.

This uses a counter to remember the footnote number. The third sentence is followed by the same footnote marker as the first.

All babies are illogical.\footnote{%
  Lewis Carroll.}\setcounter{footnoteValueSaver}{\value{footnote}}
Nobody is despised who can manage a crocodile.\footnote{%
  Captain Hook.}
Illogical persons are despised.\footnotemark[\value{footnoteValueSaver}]
Therefore, anyone who can manage a crocodile is not a baby.

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