function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Erman, Orhan & Pešić, Vladimir & Esen, Yunus & Özkan, Muhlis', 1],
    ['Esen, Yunus', 1],
    ['Martin, Peter', 2],
    ['Pešić, Vladimir', 1],
    ['Pešić, Vladimir & Chatterjee, Tapas & Bordoloi, Sabitry', 4],
    ['Sabatino, Antonio Di & Gerecke, Reinhard & Gledhill, Terence', 1],
    ['Smit, H. & Gerecke, R.', 3]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=13)',
    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);