function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Appolloni, Massimo & Smriglio, Carlo & Amati, Bruno', 1],
    ['Berg, Cornelis C. & Carauta, J. Pedro P.', 1],
    ['Brown, John & Sowerby (2), G. B.', 1],
    ['Essl, F. & Stöhr, O.', 1],
    ['Gray, John Edward', 1],
    ['Hess, Hans Ernst & Landolt, Elias & Hirzel, Rosmarie', 2],
    ['Mille, Christian & Henderson, Rosa C. & Cazères, Sylvie', 4],
    ['Moore, Charles', 1],
    ['Röding, Peter Friedrich', 2],
    ['Sowerby, James DeCarle', 3],
    ['Suh, Soo-Jung', 3],
    ['Turner, Ian M.', 6],
    ['Verloove, Filip', 1],
    ['Wang, Guoquan & Wei, Suigai & Yang, Ding', 1],
    ['Woodring, W. P.', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=29)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 15, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);