function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Denk, Thomas & Sami, Marco & Teodoridis, Vasilis', 1],
    ['Fiorito, Serena & Epifano, Francesco & Preziuso, Francesca', 1],
    ['Hess, Hans Ernst & Landolt, Elias & Hirzel, Rosmarie', 2],
    ['Info Flora', 2],
    ['Jarvis, Charlie', 1],
    ['Jiang, Jianhang & Ji, Ying & Li, Jianqiang & Zhang, Yanjun', 1],
    ['Konrad Lauber & Gerhart Wagner & Andreas Gygax', 2],
    ['Linnaeus, Carolus', 1],
    ['Liu, Shaoxiong & Liu, Linjian & Huang, Xiaofang & Zhu, Yuye', 3],
    ['Xu, Yanqin & Liu, Linjian & Liu, Shaoxiong & He, Yiming', 5],
    ['Zhang, Yanjun & Dang, Haishan & Li, Jianqiang & Wang, Ying', 1],
    ['Zhang, Yanjun & Dang, Haishan & Li, Shengyu & Li, Jianqiang', 5]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=25)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 12, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);