First Observation of the Charmless Baryonic Decay B^{+}→Λ[over ¯]pp[over ¯]p. - Aaij R; Abdelmotteleb ASW; Abellan Beteta C; Abudinén F; Ackernley T; Adefisoye AA; Adeva B; Adinolfi M; Adlarson P; Agapopoulou C; Aidala CA; Ajaltouni Z; et al. (Physical review letters, 2025)