function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Batelka, Jan & Hájek, Jiří', 7],
    ['Bologna, M. A. & Pinto, J. D.', 2],
    ['Pan, Zhao & Ren, Guo-Dong', 3],
    ['Pan, Zhao & Ren, Guodong', 2],
    ['Yang, Yu-Xia & Ren, Guo-Dong', 5]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=19)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 5, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);