The Inlatio for the feast of St. James the Great followed by the Sanctus, sung by Ensemble Organum from from Chant Mozarabe: Cathédrale de Tolède (XVe siècle). (Video by yours truly)
The Mozarabic Inlatio, or Illatio, corresponds to the Roman Preface; as Dom Fernand Cabrol says of them (in his The Mass of the Western Rites): "hardly a Mass but has its own; some of them comprise many columns of text, and if they were sung, these must have lasted at least half an hour. We will attempt presently to discover their authors. But we may say at once that they form a dogmatic collection which is priceless for the study of theological history in Spain during the Middle Ages, and a collection which, it must be confessed, has as yet been but little studied. It contains pages which do honor to the learning, the depth, and the culture of Spanish theologians from the fifth-ninth centuries." Here is an excerpt from the Catholic Encyclopedia's article on the Mozarabic Rite:
"The Illatio or Inlatio. This is called Praefatio in the Roman and Contestatio or Immolatio in the Gallican. With the Post-Sanctus it forms St. Isidore's fifth prayer. There are proper Illationes to every Mass. The form is similar to the Roman Preface, but generally longer and more diffuse, as in the Gallican. It is preceded by a longer dialogue than the usual one [...] The Illatio ends in all manner of ways, but always leading by way of the angels to the Sanctus."This particular Inlatio (from the Omnium Offerentium) curiously has a reference to a medieval tradition, recorded in the Golden Legend, that St. James cured a paralytic on his way to execution, which caused one of the executioners, a scribe named Josiah, to convert at the spot and be martyred along with him: 'per Jesum Christum Filium tuum, Dominum nostrum: in cujus nomine electus Jacobus, cum ad passionem traheretur, paraliticum ad se clamentem curavit, atque hoc miraculo cor illudentis sibi ita compulsit, ut cum sacramentis instinctum fidei faceret ad gloriam pervenire martyrii' ("through Jesus Christ your Son, our Lord, in whose name the elect James, when he was being dragged to his passion, cured a paralytic who called out to him, and by this miracle so softened the heart of him who mocked him, as to cause him now imbued with the sacraments of faith to arrive at the glory of martyrdom.")