function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Becherer', 1],
    ['Chen, Ronglian & Zhang, Faqi & Chen, Shilong & Chi, Xiaofeng', 1],
    ['Essl, F.', 1],
    ['Essl, F. & A, Lower & A, Lower', 2],
    ['Essl, F. & Stöhr, O.', 2],
    ['Info Flora', 2],
    ['Jarvis, Charlie', 1],
    ['Konrad Lauber & Gerhart Wagner & Andreas Gygax', 2],
    ['Lee, Jong-Won & Yun, Ho-Geun & Hwang, Tae Young & Kim, Kyungmin', 1],
    ['Martinetto, Edoardo & Bertini, Adele & Mantzouka, Dimitra', 1],
    ['Stöhr, O. & Pilsl, P. & Essl, F. & Wittmann, H. & Hohla, M.', 1],
    ['Suh, Soo-Jung', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=16)',
    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);