2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/50450A short article describing the derivation of the string deviation equation: $\dotΠ^ν_τ+Π'^μ_σ=R^ν_{.αβγ}r^γ(P^β_τ\dot{x}^α+P^β_σx'^α)$.2 pages, to appear in the SUSY Encyclopaedia - KluwerHigh Energy Physics - TheoryAstrophysicsGeneral Relativity and Quantum Cosmologytext