Error writing to database: [Notice : 8] Trying to get property of non-object

Tegengekomen in:
 - bestand: /home/ntvbs/domains/ntvbs.libraries/public_html/iterations/output.class/output.class.2015-01-28.php 
 - regel: 2152<br />
<b>Notice</b>:  Trying to get property of non-object in <b>/home/ntvbs/domains/ntvbs.libraries/public_html/iterations/output.class/output.class.2015-01-28.php</b> on line <b>2158</b><br />
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<b>Notice</b>:  Trying to get property of non-object in <b>/home/ntvbs/domains/ntvbs.libraries/public_html/iterations/output.class/output.class.2015-01-28.php</b> on line <b>82</b><br />