function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Ghahari, Hassan & Mazur, Slawomir & Ostovan, Hadi', 2],
    ['Lackner, Tomas & Leschen, Richard A. B.', 2],
    ['Lackner, Tomáš', 7],
    ['Penati, Fabio', 9],
    ['Penati, Fabio & Vienna, Ppierpaolo', 1],
    ['Peschel, Rüdiger', 1],
    ['Vienna, Ppierpaolo & Penati, Fabio', 10]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=32)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 7, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);