Estimation of height difference of alignment accuracy between different epochs of measurements

Authors:
1
Latvia University of Life Sciences and Technologies

This article is about first class leveling measurements made in three campagnes in Latvia: from 1929 till 1939 ;from 1967 till 1974 ;from 2000 till 2004 in lines Kolka - Rucava, Riga - Plavinas - Riga and Ainazi - Riga. There are discused obtained elevations and changed values of them in different epochs. There is also aviable assessment about changes acomplished given.

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