function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Bursey, Joseph & Smith, Julian P. S. & Litvaitis, Marian', 1],
    ['Delogu, Valentina & Casu, Marco & Curini-Galletti, Marco', 2],
    ['Delogu, Valentina & Curini-Galletti, Marco', 6],
    ['Du Plessis, G.', 1],
    ['Faubel, A. & Warwick, R. M.', 4],
    ['Gammoudi, Mehrez & Garbouj, Myriam & Egger, Bernhard', 1],
    ['Meini, Gianluca', 5],
    ['Noreña, Carolina & Damborenea, Cristina & Brusa, Francisco', 3]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=23)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 8, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);