function begin_mailto (name, domain, title) {
  var address = name + '@' + domain;
  if(title) {
    document.write("<a href='mailto:" + address + "'>" + "<span>");
  }
  else {
    document.write("<a href='mailto:" + address + "'>" + address + "<span style='display: none;'>");
  }
}

function end_mailto() {
  document.write("</span></a>");
}

function show_abstract (id) {
  var a = document.getElementById ("abstract"+id);
  if (a.style.display == "block") {
    a.style.display = "none";
  } else {
    a.style.display = "block";
  }
}

function show_lecture_title (id) {
  var a = document.getElementById ("lecture_title"+id);
  if (a.style.display == "inline") {
    a.style.display = "none";
  } else {
    a.style.display = "inline";
  }
}



function show_bibtex (id) {
  var bibtex = document.getElementById ("bibtex" + id);
  if (bibtex.style.display == "block") {
    bibtex.style.display = "none";
  } else {
    bibtex.style.display = "block";
  }
}