Undefined array key "HTTP_ACCEPT_LANGUAGE" /home/refseek1/public_html/search2/include/func-common.php:23

substr(): Passing null to parameter #1 ($string) of type string is deprecated /home/refseek1/public_html/search2/include/func-common.php:23

Undefined array key "HTTP_ACCEPT_LANGUAGE" /home/refseek1/public_html/search2/searchdoc.php:24

substr(): Passing null to parameter #1 ($string) of type string is deprecated /home/refseek1/public_html/search2/searchdoc.php:24

issn 1980-4016 - RefSeek
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