1. This research forms part of the project “From Hardinxveld to Noordhorn - from forager to farmer” within the framework of the ‘Malta Harvest Programme’ financed by the Netherlands Organisation for Scientific Research
2. Adzes were also in use in the earlier stages of the Rössen Culture (Raetzel-Fabian 1986).
3. I owe Marjorie de Grooth the detailed references to the Langweiler 8 finds.
4. No. 5033, related to house 101, ‘house generation’ IV, meaning Modderman’s stage 1c.
5. No. 3021, related to house 52, ‘house generation’ VI, meaning Modderman’s stage 1d or late Flomborn.
6. These sites have been discovered by the amateur archaeologist A.M. Wouters. Many of his sites and site reports are considered unreliable.
7. However, no research has been done into the origin of the flat adzes found more to the north. High adzes do not occur in the north.
8. Klassen presumes for the Parow sherd (Klassen 2004, Abb. 53:A) an origin in the Rhineland. This would mean a contact distance of approx. 600 km. However, the type of decoration referred to by him as characteristic for this region also occurs, albeit rarely, in the more northern LBK habitation areas in the vicinity of Wolfsburg, in which case a distance of 150 km appears more likely. The Parow find is problematic in more respects, as the authenticity of the find site is in doubt. The sherd was found when dredging a yacht basin without archaeological supervision (Terberger & Seiler 2004).
9. For similar, but Late Neolithic issues, see Lekberg 2004.
10. Pers. comm. Izabel Devriendt.
11. It is however unclear whether this is also true for the group of Breitkeile as Lönne’s study involves other tools as well, such as adzes and axes and she did not published a table of the relation between tool type and raw material.
12. Some caution is needed with alleged river finds, if purchased from antique dealers. This regards for instance finds from the Elbe at Hamburg (Klassen 2004, Fundliste 1; Laux 1993), from the Waal near Nijmegen and from the Scheldt near Ghent. (Van der Waals 1972, G.4 and O.1).
13. Pers. comm. Izabel Devriendt.
14. See also Raemaekers et al. 2001, 18, Fig. 8 and 9
15. Collection Rijksmuseum van Oudheden, inv. nr. M 1892/11.22.
16. Collection Rijksmuseum van Oudheden, inv. nr. e 1970/2.1.
17. This statistical analysis was performed by Milco Wansleeben.
18. These results are in sharp contrast with measurements published by M. Merkel (1999) for the region northern Germany and southern Scandinavia. For the hohe durchlochte Schuhleistenkeile (type E) the lengths varies between 15,3 and 37 cm and most artefacts measures 25-30 cm. For the Breitkeile of type F the lengths are 32-49 cm, an average of 30 cm for type G and type H has lengths between 10 and 30 cm.
19. The total will not exceed 20 sites, the published sites included.
20. Personal information prof. dr. D.C.M. Raemaekers.
21. The northwestern group of Spitzhauen represents a less slender group of artefacts. The slender type with a widening of the width at the location of the shaft hole is nearly absent in this region (Brandt 1976, Abb. 1, Form B.)
22. A Mesolithic grave in Nadelwitz (Germany) has yielded a pebble hammer with a straight conical perforation, however, comparable to that of the Breitkeil (Geupel 1988). This is however rare.
23. In the older study by Hulst & Verlinde (1979) sandstone is also mentioned as a major source.
24. Approximately five examples are known, all unpublished single finds (Pers.comm.. Lutz Klassen).
25. See also Brandt 1976, 273-274.
26. Pers.comm. Izabel Devriendt.
28. A use wear study of a Geröllkeule from Hattemerbroek is in progress (Drenth & Niekus 2010, 755).