function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Jacobs, Hans-Joachim & Liebig, Wolf-Harald', 1],
    ['Jahantigh, Fatemeh & Rakhshani, Ehsan & Mokhtari, Azizollah', 1],
    ['Kumar, P. Girish & Sheela, S. & Sharma, Gaurav', 4],
    ['Madl, M.', 3],
    ['Nemkov, Pavel G.', 10],
    ['Schmid, C.', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=20)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 6, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);