function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Perreau, Michel & Lemaire, Jean-Michel', 1],
    ['Perreau, Michel & Ruzicka, Jan', 1],
    ['Schilthuizen, Menno', 1],
    ['Schilthuizen, Menno & Perreau, Michel', 19],
    ['Schilthuizen, Menno & Perreau, Michel & Njunjic, Iva', 15],
    ['Wang, Cheng-Bin & Zhou, Hong-Zhang', 17]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=54)',
    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);