Error message

• Notice: Only variables should be passed by reference in include() (line 93 of /var/www/otherSites/emergochina/sites/all/themes/bootstrap4/templates/views/nav/block--views--mdr-resource-center-nav-block.tpl.php).
• Notice: Undefined variable: image_link in include() (line 135 of /var/www/otherSites/emergochina/sites/all/themes/bootstrap4/templates/taxonomy/taxonomy-term--2394.tpl.php).