function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Kner, R.', 1],
    ['Littmann, M. W. & Burr, B. M. & Nass, P.', 1],
    ['Michael W. Littmann', 13],
    ['Ohara, Willian Massaharu & Neuhaus, Emanuel Bruno', 1],
    ['Ota, Renata Rúbia & Deprá, Gabriel de Carvalho', 1],
    ['Spix, J. B. von & Agassiz, Jean Louis Rodolphe', 2],
    ['W. Peters', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=20)',
    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);