Visits sequence evaluator in attribute grammar

I am failing to understand the "visits sequence evaluator in attribute grammar". Is it an order on instantiated tree nodes where on each visit to a node we evaluate a particular node and we may end up visiting a node more than once. Is it correct?

There are two paper that describe the visit sequence evaluator:

  • Kastens original paper
  • Joost Engelfriet & Gilberto Filè describes a type of attribute grammar where we evaluate the attribute using only one visit to a tree node