def write(models, out=None, base=None, logger=logging):
    '''
    models - one or more input Versa models from which output is generated.
    '''
    assert out is not None #Output stream required
    if not isinstance(models, list): models = [models]
    for m in models:
        for link in m.match():
            s, p, o = link[:3]
            #Skip docheader statements
            if s == (base or '') + '@docheader': continue
            if p in RESOURCE_MAPPING: p = RESOURCE_MAPPING[p]
            if o in RESOURCE_MAPPING: o = RESOURCE_MAPPING[o]
            
            if p == VERSA_TYPE_REL: p = RDF_TYPE_REL
            print(strconv(s), strconv(p), strconv(o), '.', file=out)
    return
models - one or more input Versa models from which output is generated.