UFO and paranormal researchers who study BVM apparitions say that, in many of these apparitions, "the lady" never says who she is. She doesn't tell the witness she is the Blessed Mother; that's an assumption and interpretation on the part of the witness.
This fact, and parallels to psychic, paranormal and UFO phenomena, supports the theory that BVM appearances are UFO related, not literal religious events only.
In Heavenly Lights: The Apparitions of Fatima and the UFO Phenomenon, the authors Joaquim Fernandes and Fina D'Armada also mention this. In Chapter I of the book, they begin by pointing out that the lady appearing to the child witness Lucia didn't say who or what she was; the assumption it was of course the Virgin Mary was made by the deeply religious people in the area.
They quote Antonio dos Santos, Lucia's father, who said of the apparition's origins:
"If the kids saw a woman dressed in white, who else could she be but Our Lady?"
Lucia's mother questioned her about the visitation:
"Lucia, I heard it said that you saw Our Lady at Cova da Iria," her mother asked.
Lucia responded with:
"I never said that it was Our Lady -- rather, a small, pretty lady."
Visitations of ladies, often dressed in white, that come from the heavens, go back thousands of years; predating Christianity. The BVM phenomena cannot be considered in such strict and narrow terms as purely a literal religious phenomenon, as the authors of Heavenly Lights write, these apparitions are neither literally religious, nor are they to be dismissed as delusions:
Between the two extremes of irrational pity and rational intolerance, viewed in the long tradition of "the manque," there lies a vast no-man's land, where the practice of a "third way" is the beginning to find legitimacy in academic circles.