CronJob in Virtual Dedicated Server

[dafer]

Hi all

I need to know if this command to cron is correct for the reason that it appear to be invalid or not working fine. The pat to the PHP script is /usr/bin/php and the path to my own PHP script is /var/www/vhosts/my_domain.com/httpsdocs/support/email-pop.php
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/usr/bin/php /var/www/vhosts/my_domain.com/httpsdocs/support/email-pop.php
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I have separated the script to php and to the file, but without results.

I have a virtual dedicated server in godaddy and I using Plesk 8.0
If anybody can help me or anybody have a vds in godaddy and can help me, very welcome.

Thanks all