function drawChartTreatmentsPerSource() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['European Journal of Taxonomy', 2],
    ['Geodiversitas', 6],
    ['Journal of Natural History', 3],
    ['Marine Biodiversity', 1],
    ['Munis Entomology & Zoology', 2],
    ['Palaeodiversity', 1],
    ['Proceedings of the Japanese Society of Systematic Zoology', 1],
    ['Reports of Science Research Voyage of H. M. S. Challenger. Zoology', 2],
    ['Species Diversity', 1],
    ['Zitteliana', 3],
    ['ZooKeys', 1],
    ['Zoological Journal of the Linnean Society', 6],
    ['Zoological Science', 1],
    ['Zoological studies', 2],
    ['Zootaxa', 29]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Journal (n=61)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerSource', 'pie', 15, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerSource'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerSource);