function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Bleeker, Pieter', 2],
    ['Day, F.', 1],
    ['De Vis, Charles Walter', 2],
    ['Ghahari, H. & Bunalski, M.', 1],
    ['Gilchrist, J. D. F. & Thompson, W. Wardlaw', 1],
    ['Gudger, E. W.', 1],
    ['Guichenot, A.', 3],
    ['Háva, Jiří', 11],
    ['Klunzinger, C. B.', 1],
    ['Matsumoto, Keita & Háva, Jiří', 1],
    ['Peters, Wilhelm Carl Hartwig', 2],
    ['Ramsay, E. P. & Ogilby, J. D.', 1],
    ['Richardson, John', 3],
    ['Sauvage, H. E.', 2]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=32)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 14, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);