Schertling 1989 Thesis
Schertling 1990 paper (in German) (in German) (translation in English)

Harri Hemilä
University of Helsinki, Finland (papers on vitamin C and asthma) (papers on vitamin C and colds)

The files above are here available as additional material to:

Vitamin C and common cold-induced asthma: a systematic review and statistical analysis
Allergy, Asthma & Clinical Immunology 2013;9:46

Parts of the Schertling 1989 thesis were scanned to give make available the unabbreviated results of the study, see link above to the Methods section. The Wilcoxon tests for PEF and asthma symptoms differences between vitamin C and placebo periods are reported on p. 26-27 of the thesis.