1992年, 魯道夫馬蒂亞斯舒斯特, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, 第 V 卷, 伊州芝加哥: 菲爾德自然史博物館, →ISBN，第 x 頁:
For more than 90% of the figures (mostly drawn during 1976-1990), either a scale, or the given magnification, will allow the user to derive accurate measurements, even when these are lacking in the diagnosis.
Decomposition of 4 in the presence of cis-piperylene at room temperature results in the stereocontrolled formation of trans-cycloheptadiene 27 in 90% ee (96% ee at -78 °C).
