xf:select to store as many elements as values selected

Hello,
An xf:select enable to get multiple values like for the olac:code 
attribute in the following example :

<dc:subject xsi:type="olac:linguistic-field" olac:code="dialogue 
narrative singing"/>

But is there a way to store the following data instead :

<dc:subject xsi:type="olac:linguistic-field" olac:code="dialogue "/>
<dc:subject xsi:type="olac:linguistic-field" olac:code="narrative"/>
<dc:subject xsi:type="olac:linguistic-field" olac:code="singing"/>

Thanks,

-- 
Jean-Baptiste Pressac
Traitement et analyse de bases de données
Centre de Recherche Bretonne et Celtique
UMS 3554
20 rue Duquesne
CS 93837
29238 Brest cedex 3

tel : +33 (0)2 98 01 68 95
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