function drawChartTreatmentsPerSource() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Birkhaeuser Verlag', 5],
    ['Candollea', 6],
    ['Denkschriften der Schweizerischen Naturforschenden Gesellschaft', 2],
    ['Flora Helvetica', 3],
    ['Info Flora Schweiz', 5],
    ['Laurentius Salvius', 23],
    ['Linzer biologische Beiträge', 1],
    ['Order out of Chaos. Linnaean Plant Types and their Types', 69],
    ['Peckhamia', 2],
    ['PhytoKeys', 17],
    ['Phytotaxa', 13],
    ['Vegetatio', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Journal (n=147)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerSource', 'pie', 12, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerSource'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerSource);