7.2.10 The fn:min, fn:max, fn:avg, and fn:sum functions

Introduction
"The dynamic evaluation rules for aggregate functions"
    No such thing. Perhaps s/evaluation rules/semantics/

STA / rule (1|2|3|4)
"ItemType"
    Change all occurrences of "ItemType" to "FormalItemType".

STA / rule (1|2|3|4)
"Type0 in { ... }"
    I think the rule reads better if this premise is last.

STA / rule (1|2|3|4) / last two premises
"statEnv |- ItemTypei can be promoted to Type0      1 <= i <= n"
    I think you want *all* ItemTypes to be promotable to Type0, not just
    one. Change last line to
        statEnv |- ItemType1 can be promoted to Type0
        ...
        statEnv |- ItemTypen can be promoted to Type0

"For fn:avg, the target type Type is either ..."
"For fn:sum, the target type Type is either ..."
    s/Type/Type0/