echoing a value form a custom field for both Product page and Category page

[belsaas]

Hi!
I have made some custom fields and want to echo them in my product page.
How do we write the code? I have read the forum page and found this: Product fields that are not listed here can be used like this

<?php echo $product->COLUMN_NAME ?>

One of the custom fields are named CUSTUMS_FIELD_COMPOSER and this is stored in a table named "kpg2vm_virtuemart_customs" under the column "costum_title".
In the same table we find the another column named "virtuemart_custom_id".

In an other table, "kpg2vm_virtuemart_product_customfields", I have a columns named "custom_value" and "virtuemart_customfield_id".
I think I have to make the code with one or more of these column names?

One of the custom value are 'Benjamin Britten', it is the custom value in the column "custom_value".
How do I write the code so this value can be seen in the product page?