meta

• post > adding-custom-data-woocommerce-order-add-cart link > http://thewebfosters.com/adding-custom-data-woocommerce-order-add-cart/
• post > ajax-query-array-of-meta-wpdb link > https://github.com/aitzkovitz/formidable-checkbox-view
• post > multiple-checkboxes-in-meta-boxes link > https://www.skyverge.com/blog/wordpress-settings-api-hidden-field/
• post > add-extra-fields-to-your-product-page link > https://ppom.nmediahosting.com/product/happy-ninja/