function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Ahnelt, H.', 1],
    ['Ahnelt, Harald', 2],
    ['Eagderi, Soheil & Mouludi-Saleh, Atta & Esmaeili, Hamid Reza', 3],
    ['Kovacic, M.', 1],
    ['Nurettin Meriç & Lütfiye Eryilmaz & Müfit Özulug', 2],
    ['Sayyadzadeh, Golnaz & Esmaeili, Hamid Reza', 3],
    ['Zarei, Fatah & Esmaeili, Hamid Reza & Abbasi, Keyvan', 4]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=16)',
    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);