How to generate unique payment URL using Paypal?

How to generate unique payment URL using Paypal?

References

Reference NO 1

http://stackoverflow.com/questions/15205152/how-to-generate-unique-payment-url-using-paypal

Reference NO 2

https://www.paypal.com/cgi-bin/webscr?cmd=p/mer/cowp_summary-outside

Reference NO 3

https://developer.paypal.com/webapps/developer/docs/classic/paypal-payments-standard/integration-guide/subscribe_buttons/

Reference NO 4

https://forums.digitalpoint.com/threads/how-do-you-provide-a-download-link-after-accepting-paypal-payment.706374/

Reference NO 5

http://www.paypalobjects.com/en_US/ebook/subscriptions/integrating.html

Reference NO 6

http://quixly.com/

Reference NO 7

http://www.wendycholbi.com/how-to-create-a-customized-paypal-payment-button/

Reference NO 8

https://npmjs.org/package/paypal-recurring