/usr/share/doc/groff-base/examples/chem/ is in groff 1.21-7.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/groff-base/examples/chem/122/
/usr/share/doc/groff-base/examples/chem/122/README
/usr/share/doc/groff-base/examples/chem/122/ch2a_ethyl.chem
/usr/share/doc/groff-base/examples/chem/122/ch2b_benzene.chem
/usr/share/doc/groff-base/examples/chem/122/ch2c_benzene_right.chem
/usr/share/doc/groff-base/examples/chem/122/ch4a_stick.chem
/usr/share/doc/groff-base/examples/chem/122/ch4b_methyl_acetate.chem
/usr/share/doc/groff-base/examples/chem/122/ch4c_colon.chem
/usr/share/doc/groff-base/examples/chem/122/ch4d_HCl.H2O.chem
/usr/share/doc/groff-base/examples/chem/122/ch4e_CaSO4.2H2O.chem
/usr/share/doc/groff-base/examples/chem/122/ch4f_C.chem
/usr/share/doc/groff-base/examples/chem/122/ch4g_BP.chem
/usr/share/doc/groff-base/examples/chem/122/ch4h_methacrylate.chem
/usr/share/doc/groff-base/examples/chem/122/ch4i_cyclo.chem
/usr/share/doc/groff-base/examples/chem/122/ch4j_ring4.chem
/usr/share/doc/groff-base/examples/chem/122/ch4k_ring3.chem
/usr/share/doc/groff-base/examples/chem/122/ch4l_vertex.chem
/usr/share/doc/groff-base/examples/chem/122/ch4m_double.chem
/usr/share/doc/groff-base/examples/chem/122/ch4n_triple.chem
/usr/share/doc/groff-base/examples/chem/122/ch4o_aromatic.chem
/usr/share/doc/groff-base/examples/chem/122/ch4p_cholestanol.chem
/usr/share/doc/groff-base/examples/chem/122/ch4q_rings.chem
/usr/share/doc/groff-base/examples/chem/122/ch4r_spiro.chem
/usr/share/doc/groff-base/examples/chem/122/ch4s_heteroatoms.chem
/usr/share/doc/groff-base/examples/chem/122/ch4t_polycyclic.chem
/usr/share/doc/groff-base/examples/chem/122/ch4u_nicotine.chem
/usr/share/doc/groff-base/examples/chem/122/ch4v_histidine.chem
/usr/share/doc/groff-base/examples/chem/122/ch4w_lsd.chem
/usr/share/doc/groff-base/examples/chem/122/ch4x_anisole.chem
/usr/share/doc/groff-base/examples/chem/122/ch4y_reserpine.chem
/usr/share/doc/groff-base/examples/chem/122/ch4z1_eqn_glutamic.chem
/usr/share/doc/groff-base/examples/chem/122/ch4z2_text.chem
/usr/share/doc/groff-base/examples/chem/122/ch5a_size.chem
/usr/share/doc/groff-base/examples/chem/122/ch6a_pic.chem
/usr/share/doc/groff-base/examples/chem/122/ch6b_dna.chem
/usr/share/doc/groff-base/examples/chem/122/chAa_polymer.chem
/usr/share/doc/groff-base/examples/chem/122/chAb_vinyl_chloro.chem
/usr/share/doc/groff-base/examples/chem/122/chAc_morphine.chem
/usr/share/doc/groff-base/examples/chem/122/chAd_chlorophyll.chem
/usr/share/doc/groff-base/examples/chem/122/chAe_chair.chem
/usr/share/doc/groff-base/examples/chem/122/chAf_arrow.chem
/usr/share/doc/groff-base/examples/chem/122/chAg_circle.chem
/usr/share/doc/groff-base/examples/chem/122/chAh_brackets.chem
/usr/share/doc/groff-base/examples/chem/122/chAi_poly_vinyl_chloride.chem
/usr/share/doc/groff-base/examples/chem/122/chBa_jump.chem
/usr/share/doc/groff-base/examples/chem/122/chBb_bonds.chem
/usr/share/doc/groff-base/examples/chem/122/chBc_rings.chem
/usr/share/doc/groff-base/examples/chem/README
/usr/share/doc/groff-base/examples/chem/atp.chem
/usr/share/doc/groff-base/examples/chem/cholesterin.chem
/usr/share/doc/groff-base/examples/chem/ethamivan.chem
/usr/share/doc/groff-base/examples/chem/lsd.chem
/usr/share/doc/groff-base/examples/chem/morphine.chem
/usr/share/doc/groff-base/examples/chem/penicillin.chem
/usr/share/doc/groff-base/examples/chem/reserpine.chem