function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Habib, Kamran & Firdous, Qudsia & Sohrabi, Mohammad', 1],
    ['Iqbal, Muhammad Shahid & Usman, Muhammad & Habib, Kamran', 2],
    ['Szczepańska, Katarzyna & Kukwa, Martin & Guzow-Krzemińska, Beata', 6],
    ['Usman, Muhammad & Dyer, Paul S. & Brock, Matthias', 2],
    ['Zulfiqar, Rizwana & Asghar, Hafiza Simab & Khalid, Abdul Nasir', 3]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=14)',
    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);