29The Court has thus held that, since in certain sectors in which the activity is based essentially on manpower, a group of workers engaged in a joint activity on a permanent basis may constitute an economic entity, such an entity is capable of maintaining its identity after it has been transferred where the new employer does not merely pursue the activity in question but also takes over a major part, in terms of their numbers and skills, of the employees specially assigned by his predecessor to that task. In those circumstances, the new employer takes over a body of assets enabling him to carry on the activities or certain activities of the transferor undertaking in a stable way (Siizen, paragraph 21, Hernández Vidal and Others, paragraph 32, and Hidalgo and Others, paragraph 32).