function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Aliyev, Azer & Maharramova, Sheyda', 1],
    ['Broad, Gavin R.', 4],
    ['Ghahari, H. & Jussila, R.', 3],
    ['Ghahari, H. & Jussila, R. & I, Northwestern', 1],
    ['Kolarov, J.', 4],
    ['Riedel & Pénigot & Schwarz & Diller & Johansson & Japoshvili, G.', 2],
    ['Smith, Frederick', 1],
    ['Varga, A.', 3],
    ['Çoruh, S. & Özbek, H.', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=20)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 9, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);