\documentclass[12pt, pagenumber=false, parskip=half,% 

               fromalign=right, fromphone=false,%  

               fromemail=false, fromurl=false,%

               fromlogo=false, fromrule=false,%

               backaddress=false, %

               foldmarks=false]{scrlttr2}

%%%%%%%%%%%%%%%%%%%%

% fromalign = right (right, center) -  Absenderfeld  formatiert.

% fromrule = afteraddress, false, aftername -  ein Linie wird nach  der Adresse gesetzt.

% backaddress = true (false) - Setzen einer Rücksendeadresse für Fensterumschläge

% fromphone   = true         - Setzen der Telefonnummer des Absenders

% fromemail   = true         - Setzen der eMail-Adresse des Absenders

% fromurl     = true         - Setzen einer Homepageadresse des Absenders

% fromlogo    = true         - Absenderlogo (Firmenlogo) wird in den Brief eingefügt

%%%%%%%%%%%%%%%%%%%%

\usepackage{eurosym}

\usepackage{textcomp}

\usepackage{ulem}

\usepackage{times}

\usepackage[english]{babel}

\usepackage[utf8]{inputenc}

\renewcommand*{\raggedsignature}{\raggedright}

\setkomavar{fromname}{Dr~Christian Urban}

\setkomavar{fromaddress}{Department of Informatics\\

  King's College London\\

  Strand, London WC2R 2LS\\

  United Kingdom}

\setkomavar{signature}{Dr Christian Urban\\ co-chair of the ITP 2015 conference}

\makeatletter

\@addtoplength{firstheadvpos}{20mm}

\makeatother

\begin{document}

\def\adrentry#1#2#3

{\begin{letter}{\mbox{}}

\opening{\bigskip\textbf{Certificate for the Registration Fee for the ITP 2015 Conference in Nanjing}}

\bigskip

This is to certify that 

\begin{center}

\textbf{#1}

\end{center}

\noindent paid

\begin{flushright}

\begin{tabular}{l@{\hspace{5mm}}r}

Total: & \uuline{#2}\\

\end{tabular}

\end{flushright}

\noindent 

\if #30{for the International Conference on Interactive Theorem Proving, which took place

from 24th until 27th of August in Nanjing, China.} \fi

\if #31{for the International Conference on Interactive Theorem Proving and the Isabelle Tutorial, 

which both took place from 21st until 27th of August in Nanjing, China.} \fi 

\if #32{for the International Conference on Interactive Theorem Proving and the Coq Tutorial, 

which both took place from 24th until 29th of August in Nanjing, China.} \fi 

\if #33{for the International Conference on Interactive Theorem Proving, as well as the 

Isabelle and Coq Tutorials, which all took place from 21th until 29th of August in Nanjing, China.} \fi 

\bigskip\bigskip\bigskip

\closing{\noindent{}Yours sincerely,\bigskip\mbox{}}

\end{letter}

}

\input{participants.db}

\end{document}