function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Abdel-Dayem, Mahmoud S. & Fad, Hassan H. & El-Torkey, Ashraf M.', 1],
    ['Ghahari, H. & Hayat, R. & Tabari, M. & Ostovan, H. & Imani, S.', 1],
    ['Hájek, Jiří & Švihla, Vladimír', 3],
    ['Mirutenko, Vladyslav & Ghahari, Hassan', 5],
    ['Tshernyshev, Sergei E.', 1],
    ['Švihla, Vladimír & Mifsud, David', 2]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=13)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 6, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);