function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Denzer, Wolfgang & Manthey, Ulrich', 2],
    ['Dondorp, Esther & Denzer, Wolfgang', 2],
    ['Mahony, Stephen', 2],
    ['Manthey, U. & Wolfgang, D. & Hou, M. & Wang, X.', 9],
    ['Wang, Kai & Jiang, Ke & Ren, Jinlong & Zou, Dahu & Wu, Jiawei', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=16)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 5, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);