Sybenga J
Can J Genet Cytol. 1984 Jun;26(3):389-92. doi: 10.1139/g84-061.
Unlike adjacent I and II, alternate I and II orientations of interchange and tetrasome quadrivalents can be considered extremes within one particular population of orientations (alternate) and thus lack sufficient distinction to justify a separate taxonomic status. Within the population up to six types may be distinguished, but the biological significance of this distinction is small.
与相邻的Ⅰ和Ⅱ不同，互换和四体四价体的交替Ⅰ和Ⅱ取向可被视为一个特定取向群体（交替）中的极端情况，因此缺乏足够的差异来证明其具有独立的分类地位。在这个群体中，可区分出多达六种类型，但这种区分的生物学意义不大。
