function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Engler, Heinrich Gustav Adolf', 2],
    ['Engler, Heinrich Gustav Adolf & Krause, Johann Wilhelm', 3],
    ['Fang, Qiong & Yang, Jun & Long, Chunlin', 2],
    ['Hay, William Perry', 1],
    ['Hay, William Perry & Wise, Frederick Clunie', 5],
    ['Jarvis, Charlie', 2],
    ['Mille, Christian & Henderson, Rosa C. & Cazères, Sylvie', 1],
    ['Smith, Johannes Jacobus', 2],
    ['Wong, Sin Yeng & Joling, Jyloerica', 13]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=31)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 9, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);