A sufficient number of lessons alone, both theoreti-
cal and practical, cannot manage the matter in some sub-
jects to be mastered successfully. Another important pre-
sumption are suitable textbooks, good instrumental equin-
ment corresponding to the present state of technique and
other necessary aids, primarily the aerials photographs.
The number of lessons, practical lectures and the vo-
lume of the field works, will be of course different accor-
ding to range of the subjects and the character of students,
to those the course is determined, and according to the go-
that is to be reached. There are no insurmountable dif-
ficulties expected. As to the textbooks, we can say, that
the situation has developed very luckily recently. For
the English speaking people interested there is an excel-
lent publication of the American Society of Photogramme-
try "Manual of Photographic Interpretation", which is com-
pleted with a new publication appeared the last year "Ma-
nual of Remote Sensing". For German speaking people the
textbook by prof.Scheider "Luftbild und Luftbildinterpre-
tation" — Publishing house Walter de Gruyter. For those
who speak Russian the textbook by prof.Gospodinov "Desi-
frirovanije aerofotosnimkov" — Publishing house Nedra is
available and for French speaking students a very good
publication "Manuel de Photointerpretation" — Edition
Technip can be recommendad.
I remember only the basic textbooks. A great number
of other textbooks, manuals or auxiliary texts has been
published, many of them with a view to a certain direc-
tion - geology, geography, forest inventory and others.
I am sure that it wouldn't be amiss to publish a list of
the most important and most extensive textbooks which ap-
peared in the particular countries and in the areas of
certain language grou groups.
It can be expected that are good teachers in all
countries, who will be able to read the lessons in the
subjects in question, even though their sources of in-
formation and especially their practical knowledge cannot
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