function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Becherer', 4],
    ['Cabezudo, Baltasar & Solanas, Federico Casimiro-Soriguer', 2],
    ['Erol, Osman & Can, Levent & Küçüker, Orhan', 1],
    ['Hess, Hans Ernst & Landolt, Elias & Hirzel, Rosmarie', 4],
    ['Info Flora', 6],
    ['Jarvis, Charlie', 3],
    ['Kerndorff, H. & Pasche, E.', 3],
    ['Konrad Lauber & Gerhart Wagner & Andreas Gygax', 3],
    ['Le Brun, P.', 1],
    ['Linnaeus, Carolus', 4],
    ['Novikov, Andriy', 1],
    ['Reich, Dieter & Gutermann, Walter & Bardy, Katharina', 3],
    ['Roma-Marzio, Francesco & Harpke, Doerte & Peruzzi, Lorenzo', 1],
    ['Stöhr, O. & Pilsl, P. & Essl, F. & Hohla, M. & Schröck, C.', 3],
    ['Yüzbaşioğlu, Sirri & Özhatay, Neriman', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=40)',
    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);