1. Andersson E, Jansson R, Lindgren D (1974) Some results from second generation crossings involving inbreeding in Norway spruce (Picea abies). Silvae Genet 23:34–43
2. Bingham RT (1973) Possibilities for improvement of western white pine by inbreeding. USDA For Serv Res Pap INT-144
3. Bishir J, Pepper WD (1977) Estimation of numbers of embryonic lethal alleles in conifers. 1. Self-pollinated seed. Silvae Genet 26:50–54
4. Bramlett DL, Popham TW (1971) Model relating unsound seed and embryonic lethal alleles in self-pollinated pines. Silvae Genet 20:192–193
5. Brown IR (1971) Flowering and seed production in grafted clones of Scots pine. Silvae Genet 20:121–132