Specific gravity of wood of black spruce (Picea Mariana Mill. B.S.P.) grown on a hylocomium-cornus site type / J. Risi, E. Zeller. - Québec : Université, 1960
. - 70 p. : il. ; 23 cm. - (Contribution) . 6
. - 70 p. : il. ; 23 cm. - (Contribution) . 6