Two questions about choiceBranchKey

[Roger L Costello]

I read one character from the input and use it to populate 
Continuation_Record_Number:

<xs:element name="Continuation_Record_Number" type="validString" 
dfdl:lengthKind="explicit" dfdl:length="1" />

If the value that was read is 0 or 1, then the remaining input contains data 
for vhf_navaids. If the value is greater than 1, then the remaining input 
contains data for vhf_navaids_continuation:

<xs:choice dfdl:choiceDispatchKey='{Continuation_Record_Number}'>
    <xs:sequence dfdl:choiceBranchKey="0 1">
        <xs:group ref="vhf-navaids"/>
    </xs:sequence>
    <xs:sequence dfdl:choiceBranchKey="greater than 1">
        <xs:group ref="vhf-navaids-continuation"/>
    </xs:sequence>
</xs:choice>

Two questions:

1. The specification says that the value of choiceBranchKey is a "List of DFDL 
String Literals". Is the correct way to express the list 0, 1 like this:

    dfdl:choiceBranchKey="0 1"

2. How to express this value for choiceBranchKey: any value greater than 1