# Make footcite's superscript reference have a bracket around it

I am writing a mathematical essay, and I am using \footcite{} as it is the required citation format, but the superscript looks very similar to an exponent when next to an equation. I have seen this page, but the solution doesn't seem to work for me. Whether it's simple incompetence on my part, or a different case, any help is appreciated.

MWE Below:

\documentclass{article}
\usepackage[md]{titlesec}

\usepackage{filecontents}
\usepackage[style=mla, citestyle=authoryear-comp, backend=bibtex]{biblatex}

\begin{filecontents}{myreferences.bib}
@article{einstein,
author =       "Albert Einstein",
title =        "{Zur Elektrodynamik bewegter K{\"o}rper}. ({German})
[{On} the electrodynamics of moving bodies]",
journal =      "Annalen der Physik",
volume =       "322",
number =       "10",
pages =        "891--921",
year =         "1905",
DOI =          "http://dx.doi.org/10.1002/andp.19053221004"
}

@article{Lagarias,
author =       "Jeffery C. Lagarias",
title =        "{Euler's constant: Euler's work and modern developments}",
journal =      "Bulletin of the American Mathematical Society",
volume =       "50",
pages =        "556",
year =         "2013",
DOI =          "10.1090/s0273-0979-2013-01423-x"
}

@inbook{Leonhard,
author    = "Leonhard Euler",
title     = "{Tentamen novae theoriae musicae ex certissimis harmoniae principiis dilucide expositae}. ({Latin}) [{An illuminating} new theory of music {most exposed} to the principles of harmony]",
chapter     = "Chapter VII. De Variorum Intervallorum Receptis Appelationibus",
year      = "1739",
pages     = "102--112",
}

@inbook{Stifel,
author    = "Michael Stifel",
title     = "{Arithmetica Integra}. ({Latin})[ Integrated Arithmetic]",
pages     = "8--9",
year      = "1544",
publisher     = "Johann Petreium",
}

@inbook{Leiss,
author    = "Ernst L. Leiss",
title     = "A Programmer's Companion to Algorithm Analysis",
year      = "2006",
publisher     = "CRC Press",
pages     = "28",
ISBN     = "9781584886730"
}

@inbook{Rowan,
author    = "Rowan Garnier and John Taylor",
title     = "Discrete Mathematics, Proofs, Structures, and Applications",
version     = "3",
year      = "2009",
publisher     = "CRC Press",
pages     = "620",
ISBN     = "9781439812808"
}

@inbook{Goodrich,
author    = "Michael T. Goodrich and Roberto Tamassia",
title     = "Algorithm Design: Foundations, Analysis, and Internet Examples",
year      = "2002",
publisher     = "John Wiley \& Sons",
pages     = "23",
}

@inbook{Knuth,
author    = "Donald E. Knuth",
title     = "Fundamental Algorithms, The Art of Computer Programming",
version     = "3",
year      = "1997",
pages     = "11",
ISBN      = "9780321635747"
}

@inbook{Fred,
author    = "Fred Roberts and Barry Tesman",
title     = "Fundamental Algorithms, The Art of Computer Programming",
version     = "2",
year      = "2009",
publisher     = "CRC Press",
pages     = "206",
ISBN      = "9781420099836"
}

@inbook{Steven,
author    = "Steven S. Skiena",
title     = "The Algorithm Design Manual",
version     = "2",
year      = "2009",
publisher     = "Springer Press",
pages     = "78",
ISBN      = "9781848000698"
}

@inbook{campbell,
title={The Musician's Guide to Acoustics},
author={Murray Campbell and Clive Greated},
isbn={9780191591679},
year={1994},
publisher={OUP Oxford}
}

@inbook{france,
title={Introduction to Physical Education and Sport Science},
author={Robert C. France},
isbn={9781418055295},
pages={282},
lccn={2008930301},
year={2008},
publisher={Cengage Learning}
}

@online{Eulernamed,
author    = "Wikipedia",
title     = "{List of things named after Leonhard Euler}",
year    = "2007",
url       = "{https://en.wikipedia.org/wiki/List_of_things_named_after_Leonhard_Euler.html}"
}

@online{Powerset,
author    = "Wikipedia",
title     = "{Power set}",
year    = "2015",
url       = "{https://en.wikipedia.org/wiki/Power_set.html}"
}

@online{Comptree,
author    = "Paul E. Black",
title     = "{Complete Binary Tree}",
year    = "2016",
}
\end{filecontents}

\begin{document}
The Binary Logarithm ($\log_2 n$) is the power to which the number $2$ must
be raised to obtain the value $n$ (for any real number $x$). Ergo, $x = \log_2 n \Longleftrightarrow 2^x = n$ The first use of the binary logarithm was in
music theory, by Leonhard Euler ~\footcite{Leonhard}, who is the only
mathematician with two numbers named after him~\footcite{Eulernamed} (Euler's
Number ($e \approx 2.71828$ ~\footcite{Eulernamed}) and the Euler-Mascheroni
constant ($\gamma \approx 0.57721$) ~\footcite{Lagarias}). However, the first
known table of binary logarithms is credited to Michael Stifel
\footcite{Stifel}. Stifel was also the first to use the term "exponent" and
includes the $q^m \times q^n = q^{m+n}$ and $\frac{q^m}{q^n} = q^{m-n}$
~\footcite{Stifel} rules in his book \emph{Arithmetica Integra}. Today's form of
the binary logarithm (which applies to any number, and not necessarily a power
$n$ to base $2$ ($2^n$) was established by Euler in 1739, in a table of binary logarithms for integers $1$ to $8$, to 7 decimal digits of accuracy\footcite{Leonhard}. has long been of use with computations, as $2^n$ is
commonly used for the classification of $1$s and $0$s, mainly as Boolean values.
\end{document}


A slight modification of Add square brackets to footfullcite in beamer

To add the square brackets, you can alter the definition of

• \@makefnmark for the number displayed in the text

• \@makefntext for the number displayed in the footnote

\documentclass{article}
\usepackage[md]{titlesec}

\usepackage{filecontents}
\usepackage[style=mla, citestyle=authoryear-comp, backend=bibtex]{biblatex}

\begin{filecontents}{myreferences.bib}
@article{einstein,
author =       "Albert Einstein",
title =        "{Zur Elektrodynamik bewegter K{\"o}rper}. ({German})
[{On} the electrodynamics of moving bodies]",
journal =      "Annalen der Physik",
volume =       "322",
number =       "10",
pages =        "891--921",
year =         "1905",
DOI =          "http://dx.doi.org/10.1002/andp.19053221004"
}
\end{filecontents}

\makeatletter
\renewcommand\@makefnmark{\textsuperscript{[\@thefnmark]}}
\renewcommand\@makefntext[1]{\textsuperscript{[\@thefnmark]}\enspace #1}
\makeatother