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diff --git a/README b/README
index 824bb38..2686785 100644
--- a/README
+++ b/README
@@ -6,3 +6,16 @@ version 1) Teleauskunft 1188 from 1992, (April-June)
 version 2) Teleauskunft 1188 Telefon-Teilnehmer, Oktober 1995 / Telefon-Teilnehmer Gesamtausgabe from 1995/1996
 version 3) Telefonbuch für Deutschland, Version 1.0 1996 through DasTelefonbuch, Deutschland, Herbst 2003
 version 4) DasTelefonbuch, Map&Route, Frühjahr 2004 until now
+
+version 1
+=========
+
+Notes: Strings are encoded in cp437, those inside records stored in 7-bit packed encoding. Only the .001 files on each CD are interesting.
+
+Each file consists of a standard header and a number of pages, with pages starting at 0x800, being spaced at 0x2000 steps.
+
+The header's important values are (uint16_t*)0x40 number of pages, (uint32_t*)0x42 total number of records in file and a \0 separated list of gasse, city, zip and prefix, starting at 0xe8.
+
+Each page can either be a "normal" one, with phone entries or a "blob" one, with multi line records, being referenced from "normal" pages inside the same file. It starts with a flag (uint8_t*)0x00, a size of blob's contents (i.e. if != 0, this is a blob page) at (uint16_t*)0x02, a count of records in that page at (uint16_t*)0x04 and for each record a pointer into this page (plus offset 0x0e), starting at 0x0e.
+
+Each record