function drawChartTreatmentsPerAuthor() {
  var chartData = google.visualization.arrayToDataTable([
    ['Series', 'Number of Treatments'],
    ['Chetverikov, Philipp E.', 2],
    ['Chetverikov, Philipp E. & Petanović, Radmila U.', 1],
    ['Jočić, Ivona & Petanović, Radmila & Vidović, Biljana', 1],
    ['LIU, DONG & YI, TIAN-CI & XU, YUN & ZHANG, ZHI-QIANG', 2],
    ['Skoracka, Anna & Macuk, Lucyna & Rakowski, Wojciech', 2],
    ['Soika, Grażyna & Kozak, Marcin', 1],
    ['Stalažs, Arturs & Turka, Ināra', 1]
  ]);
  var chartOptions = {
    pieHole: 0,
    title: 'Treatments per Author (n=10)',
    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);