[Clause] Schema [Description] A URI that identifies a particular P3 proposal vocabulary [Applies to] proposal [Required in Every Proposal] yes [Default Type of Label] URI [May be Defined in Vocabulary] 
no
y e s
n o
n o , b u t q u a l i f i e r a n d c a t e g o r y c o m p o n e n t s m a y b e