function drawChartTreatmentsPerSource() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Acarologia', 2],
    ['Ecologica Montenegrina', 6],
    ['Ent Mitt Zool Mus Hambg', 1],
    ['Journal of Natural History', 2],
    ['Persian Journal of Acarology', 16],
    ['Veröffentlichungen des Instituts für Meeresforschung Bremerhaven', 3],
    ['Zootaxa', 20]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Journal (n=50)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerSource', 'pie', 7, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerSource'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerSource);