function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Avgin, Sakine Serap', 1],
    ['Azadbakhsh, Saeed & Nozari, Jamasb', 1],
    ['Chittaro, Yannick & Claude, François & Hoess, René', 1],
    ['Guéorguiev, B.', 4],
    ['Herger, Peter & Germann, Christoph', 1],
    ['Hoess, René', 2],
    ['Hristovski, Slavčo & Guéorguiev, Borislav', 3],
    ['Kostova, Rumyana & Gueorguiev, Borislav', 2],
    ['Neri, Paolo & Toledano, Luca', 3],
    ['Toledano, Luca', 3]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=21)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 10, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);