function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Becherer', 1],
    ['Brullo, Salvatore & Brullo, Cristian & Cambria, Salvatore', 1],
    ['Cabezudo, Baltasar & Solanas, Federico Casimiro-Soriguer', 2],
    ['Friis, Else Marie & Crane, Peter R. & Pedersen, Kaj Raunsgaard', 3],
    ['Hess, Hans Ernst & Landolt, Elias & Hirzel, Rosmarie', 3],
    ['Info Flora', 1],
    ['Jarvis, Charlie', 3],
    ['Jin, Wei-Yin & Liu, Bing & Zhang, Shou-Zhou & Wan, Tao', 1],
    ['Konrad Lauber & Gerhart Wagner & Andreas Gygax', 1],
    ['Markgraf, Friedrich', 2],
    ['Martin, Jon H. & Lau, Clive S. K.', 1],
    ['Rather, Zubair Ahmad & Khuroo, Anzar Ahmad', 1],
    ['Sokoloff, Paul C. & Freebury, Colin E. & Hamilton, Paul B.', 2]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=22)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 13, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);