\documentclass[stationery]{hduthesis}

\usepackage{lipsum}
\RequirePackage [ mono = false ] {libertine}

\DocInfo
  {
    title      = Recommendation Letter for SAN Chi Nan,
    author     =  YIP Tsz Ching,
    affliction = {Physics Department, Hangzhou Dianzi University},
    date       = {25\textsuperscript{th} November, 2024},
    tel        = (852) 3141-5926,
    mail       = xiamyphys@gmail.com
  }

\begin{document}

\maketitle

To whom it may concern:

\lipsum[1-2]

\vspace{\baselineskip} \raggedleft

Sincerely yours ,\\[2ex]
\includegraphics[ height = 2em ]{hdutitle}\\[2ex]
Professor of Department of Physics\\
Room \meta{int}, Building \meta{int}, Hangzhou Dianzi University

\end{document}