Which do you think is greater over the lifetime of a clinical terminology system, the original cost of the purchase or the cost of upgrades and maintenance to the terminology, as well as the interfaces between the terminology and other clinical information systems?

Which do you think is greater over the lifetime of a clinical terminology system, the original cost of the purchase or the cost of upgrades and maintenance to the terminology, as well as the interfaces between the terminology and other clinical information systems?

I need two references, one article, and the textbook name GUIDE TO HEALTH INFORMATICS THIRD EDITION. I will send a picture of the book.