Greek letters must be written using the following three letter abbreviations:
α alf ι iot ρ rho β bet κ kap σ sig γ gam λ lam τ tau δ del µ mu. υ ups ε eps ν nu. φ phi ζ zet ξ ksi χ khi η eta o omi ψ psi θ tet π pi. ω ome
