function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Chen, Juanjuan & Schmelz, Ruediger M. & Xie, Zhicai', 1],
    ['Chen, Juanjuan & Schmelz, Rüdiger M. & Zhang, Zuxu & Xie, Zhicai', 2],
    ['Christoffersen, Martin L.', 1],
    ['Dózsa-Farkas, Klára & Hong, Yong', 3],
    ['Schmelz, R. M. & Römbke, J.', 6],
    ['Schmelz, Rüdiger M. & Jocque, Merlijn & Collado, Rut', 3]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=16)',
    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);