Subquiver

A subquiver $Δ$ of a quiver $Γ$ is a a quiver such that quiv

Δ 𝐸 \subseteq Γ 𝐸, Δ 𝑉 \subseteq Γ 𝐸, Δ 𝑠 = Γ 𝑠 ↾ Δ 𝐸, Δ 𝑡 = Γ 𝑡 ↾ Δ 𝐸;

in other words, we have an inclusion $𝜄 : Δ ↪ Γ$ .