database modeling

Hello everybody!
I am a beginner in MongoDB. For academic work, I would like to design a database to manage a university. I tried to do this for the other entities (collections) but I have difficulty managing the relationship between Field and Student. I submit my diagram here for appreciation and correction.

etablissement:{nom; String,
type: String,
PA: [{ nom; String,
poste: String,
contact: String}
]
filiere:{ code: String,
intitule: String,
etablissement: ObjectId,
ues:[ObjectId],
etudiant: [ObjectId]
}
ues :{ code: String,
intitule: String,
description: String,
enseignants:[ObjectId],
filiere:[ObjectId]
}
enseignants:{ nom: String,
prenom; String,
specialite: String,
grade: String,
contact: String,
ues: [ObjactId]
}
etudiants: { nom: String,
prenom: String,
date_nais: Date,
contact: String,
niveau:{
cycle: String,
annee: String
},
filiere:
}