function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Jezek, Jan & Chvojka, Pavel & Manko, Peter & Obona, Jozef', 7],
    ['Jezek, Jan & Manko, Peter & Obona, Jozef', 6],
    ['Ježek, Jan', 9],
    ['Ježek, Jan & Hájek, Josef', 7],
    ['Ježek, Jan & Manko, Peter & Oboňa, Jozef', 9],
    ['Ježek, Jan & Oboňa, Jozef & Manko, Peter', 2],
    ['Kvifte, Gunnar Mikalsen & Andersen, Trond', 1],
    ['Omelková, Markéta & Ježek, Jan', 9],
    ['Tkoč, Michal & Pecharová, Martina & Ježek, Jan', 3],
    ['Wagner, Rüdiger & Andrade, Rui & Gonçalves, Ana', 4]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=57)',
    fontSize: 'automatic',
    doWeHaveDanglingCommas: 'No ;-)'
  };
  if (window.customizeGoogleChartOptions)
    customizeGoogleChartOptions(chartOptions, 'TreatmentsPerAuthor', 'pie', 10, 0);
  var chart = new google.visualization.PieChart(document.getElementById('chartDivTreatmentsPerAuthor'));
  chart.draw(chartData, chartOptions);
}
google.load('visualization', '1', {'packages': ['corechart']});
google.setOnLoadCallback(drawChartTreatmentsPerAuthor);