function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['DeFilipps, Robert A. & Krupnick, Gary A.', 1],
    ['Diels, Friedrich Ludwig Emil', 1],
    ['Hoogland, Ruurd Dirk', 2],
    ['Jarvis, Charlie', 1],
    ['Leenhouts, Pieter Willem', 3],
    ['Linnaeus, Carolus', 1],
    ['Mabberley, David John', 1],
    ['Turner, Ian M.', 2],
    ['Wijnands, Dirk Onno & Heniger, Johannes & Veldkamp, Jan Frederik', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=13)',
    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);