The title of this work is: The letters of Baron Francis X. Zach, Director of the Observatory of Gotha-Seeberg, and his successors Bernard von Lindenau to Father Martin Alois David, Assistant Astronomer and Director of the Royal Observatory of Prague from 1791 till 1816. The study contains a) 62 letters of Zach, b) 9 letters of Lindenau, all of them being of astronomical interest and kept in the records of the Observatory of Prague (IV.), and c) notes of David (III.) as they were written during his visit at Zach 1789 and 1801. - In his introduction, the editor follows the personal and literary contacts of David with Zach (I.). The statistics of the correspondence (II.) reports on a) the letters published in the work, b) on the letters of Zach and Lindenau mentioned only in David´s diaries or partly published in the reviews on account of their scientific value, an c) on a list of letters of David sent to Zach and Lindenau that have nor been found till today, being known from David´s diaries only. In the V. part there is a list of essays written by David and Adam Bittner. Assistant Astronomer of Prague Observatory, which were published in reviews edited by Zach and Lindenau, and a list of Zach´s reports on David´s essays.
This catalogue is computer-based and issued in collaboration with the CDS in Strasbourg. The outlay of the catalogue will be described, particularly the tracer system for data base handling. A new examination of cluster appearances on survey charts has been entered in the 1983 edition. Various parameters will be compared and their accuracy discussed.
In May 1980, the WEDOC-1 was carried out covering 14 simultaneous stations and establishing a first link between observatories in Western and Eastern Europe. In order to improve the results of WEDOC-1 using a better station configuration and refined software and calibration techniques a second campaign WEDOC-2 was initiated by Graz (Austria) and Penc (Hungary). The configuration comprized 27 stations in 18 countries which carried out simultaneous Doppler observations from September 6th to 16th, 1983. Four different calibration campaigns were used to estimate receiver and program biases. Station coordinates have been computed by means of the programs GEODOP in Graz and SADOSA in Budapest. and V maje 1980 g. byla osuščestvlena kampanija "WEDOC-1", v kotoruju vključilos' 14 stancij. Vpervyje osuščestvlena privjazka meždu observatorijami Zapadnoj i Vostočnoj Jevropy. Čtoby ulučšit' rezul'taty kampanii "WEDOC-1" vtoraja kampanija "WEDOC-2" byla osuščestvlena observatorijami Grac (Avstrija) i Penc (Vengrija) s ulučšennoj konfiguracijej stancij, ulučšennym obespečenijem i technikoj kalibrovki. Konfiguracija vključila 27 stancij v 18 stranach, kotoryje vypolnili sinchronnyje nabljudenija s 6 - 16 sentjabrja 1983 g. Primenili četyre raznych kampanii kalibrovki, čtoby ocenit' pograšnosti prijemnika i vyčislitelnoj programmy. Koordinaty stancij byli vyčisleny s pomošč'ju programm GEODOP v Grace i SADOSA v Budapešte.