document.write('<p>');
document.write('<span style= "color: green; font-weight: bold">Recommended reading:</span>');
document.write(' &nbsp;  &nbsp; <a href = "http://www.horizonpress.com/probioticsbooks">Probiotics</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/environmentalbooks">Environmental Microbiology</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/bacteriology">Bacteriology</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/medicalbooks">Microbial Pathogenesis</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/molbiobooks">Molecular Biology</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/virology">Virology</a>');
document.write(' &nbsp; | &nbsp; <a href = "http://www.horizonpress.com/pcrbooks">PCR</a>');