Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1977)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1978)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1979)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1980)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1981)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1983)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1984)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1985)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1989)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1991)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1993)

Syllogeus - National Museum of Natural Sciences (Canada) (National Museum of Natural Sciences, 1995)

Symbolae ad floram Brasiliae centralis cognoscendam - Warming, Eugenius, 1841 -1924 (Naturhistoriske Forening i Kjöbenhavn, 1867)

Symbolae Antillanae,seu, Fundamenta florae Indiae Occidentalis - Urban, Ignaz, 1848 -1931 (Fratres Borntraeger ;Paul Klincksieck, 1899)

Symbolae Antillanae,seu, Fundamenta florae Indiae Occidentalis - Urban, Ignaz, 1848 -1931 (Fratres Borntraeger ;Paul Klincksieck, 1898)

Symbolae Antillanae,seu, Fundamenta florae Indiae Occidentalis - Urban, Ignaz, 1848 -1931 (Fratres Borntraeger ;Paul Klincksieck, 1903)

Symbolae Antillanae,seu, Fundamenta florae Indiae Occidentalis - Urban, Ignaz, 1848 -1931 (Fratres Borntraeger ;Paul Klincksieck, 1920)

Symbolae Antillanae,seu, Fundamenta florae Indiae Occidentalis - Urban, Ignaz, 1848 -1931 (Fratres Borntraeger ;Paul Klincksieck, 1923)

Symbolae sinicae :botanische Ergebnisse der Expedition der Akademie der Wissenschaften in Wein nach Südwest-China, 1914-1918 - Handel-Mazzetti, Heinrich, Freiherr von, 1882 -1940 (J. Springer, 1929)

Symbolae sinicae :botanische Ergebnisse der Expedition der Akademie der Wissenschaften in Wein nach Südwest-China, 1914-1918 - Handel-Mazzetti, Heinrich, Freiherr von, 1882 -1940 (J. Springer, 1936)

Synonymia botanica locupletissima generum, sectionum vel subgenerum ad finem anni 1858 promulgatorum : In forma conspectus systematici totius regni vegetabilis schemati Endlicheriano adaptati - Pfeiffer, Louis (Ludwig Georg Karl), 1805 -1877 (Sumptibus T. Fischer, 1870)

Synopsis der mitteleuropaïschen flora - Graebner, Paul, 1871 -1933 (W. Engelmann, 1896)