Ehlers P. Nikolai (Co-author). "Mit der Regelmäßigkeit eines Schweizer Uhrwerks: Versuche, Charterfluggesellschaften bei Zusammenbrüchen von Reiseveranstaltern in Anspruch zu nehmen" (Comments on attempts of stranded passengers to hold charter carriers liable in case of bankruptcies of tour operators - Contribution to: Luftverkehrsrecht im Wandel, Liber amicorum for Werner Guldimann, dedicated by the members of the Luftrechtsforum, Editors: Wolf Müller-Rostin and Ronald Schmid, Neuwied/Kriftel/Berlin, 1997, 39-57).
Ehlers P. Nikolai (Co-author). Aviation in Europe – A Multiple-Challenge Industry (Contribution to: Annals of Air and Space Law, Editor-in-Chief: Paul Stephen Dempsey, – Vol. XXIX, 493 – 500, 2004, Carswell, Toronto).
Ehlers P. Nikolai (Co-author). Aviation Liability Handbook 2007 (CD), compiled by Condon & Forsyth LLP on behalf of and in association with the International Union of Aviation Insurers, 2007, 165-169.
Ehlers P. Nikolai (Co-author). Cologne Compendium on Air Law in Europe; Editor: Professor Dr. Stephan Hobe, LL.M., Nicolai von Ruckteschell and David Heffernan, Carl Heymanns Verlag, 2013, 1051-1076.
Ehlers P. Nikolai (Co-author). Comments on a Decision of the German Federal Supreme Court on the Conversion of the Poincaré Franc (Contribution to: Annals of Air and Space Law, Editor: Nicolas Mateesco Matte, Vol. XII, 453-454, 1987, Carswell, Toronto/Pedone, Paris).
Ehlers P. Nikolai (Co-author). Erläuterungen zu bestimmten Vorschriften des Warschauer Abkommens und der Zusatzabkommen von Den Haag, Guatemala City, Montreal und Guadalajara (Commentary to certain provisions of the Warsaw Convention, the Hague Protocol, the Guatemala City and Montreal Protocols and the Guadalajara Convention - Contribution to: Giemulla/Schmid, Warschauer Abkommen und Zusatzabkommen von Guadalajara - Internationales Lufttransportrecht, loose-leaf, Kommentator-Verlag, Frankfurt).
Ehlers P. Nikolai (Co-author). Erläuterungen zum Warschauer Abkommen und den Zusatzabkommen (Commentary of the Warsaw Convention and the supplementary agreements - Contribution to: Bülow-Böckstiegel, Der Internationale Rechtsverkehr in Zivil- und Handelssachen, loose-leaf, Beck-Verlag, Munich).
Ehlers P. Nikolai (Co-author). Kölner Kompendium des Luftrechts, Werk in drei Bänden; Editor: Professor Dr. Stephan Hobe, LL.M. and Nicolai von Ruckteschell, Carl Heymanns Verlag, 2010, Vol. 3, 345-362.
Ehlers P. Nikolai (Co-author). The Privatisation of the German ATC Organisation DFS, Who’s Who Legal, The International Who’s Who of Aviation Lawyers 2006, July 2006, 13 – 14 (together with Thorsten Ebermann).
Ehlers P. Nikolai (Co-author). Warsaw Convention - Commentary, editors: Giemulla/Schmid/Ehlers/Müller-Rostin, looseleaf, Kluwer Law International, The Hayne/London/Boston.
Ehlers P. Nikolai (Co-author). “Forum non conveniens. Neuere Entwicklungen in der amerikanischen Rechtsprechung und das Verhältnis zum Warschauer Haftungssystem“ (Forum non conveniens. Recent Developments in American Jurisdiction and the Warsaw Liability System – Contribution to: Das Luftverkehrsrecht vor neuen Herausforderungen, Liber amicorum for Edgar Ruhwedel, dedicated by the members of the Luftrechtsforum, Editors: Wolf Müller-Rostin and Ronald Schmid, München/Unterschleißheim, 2004, 99-115).
Ehlers P. Nikolai (Co-author). „Master Program in Canada; McGill University, Institute of Air and Space Law“ (Contribution to: Deutsch-Amerikanische Juristenvereinigung e. V., USA-Studienführer für Juristen, 3rd Edition, Bonn 1990, 163-167).
Ehlers P. Nikolai (Co-author). „Products Liability in Germany Today and Tomorrow“ (Contribution to: Annals of Air and Space Law, Editor: Nicolas Mateesco Matte, Vol. XVI, 41-55, 1991, Carswell, Toronto/Pedone, Paris).
Ehlers P. Nikolai (Co-author). „The Warsaw Convention - Nothing left but a shell? Weaknesses of the planned new IATA Intercarrier Agreement“; Lloyd’s Aviation Law, vol. 15, no. 4, February 15, 1996, 1 - 5 (together with the other members of the Luftrechtsforum).
Ehlers P. Nikolai. Computerized reservations systems in the air transport industry (1988, Kluwer, Deventer / Antwerp / London / Frankfurt / Boston / New York).
Ehlers P. Nikolai. German Aviation: Crisis and Renewal; Editorial for the Guide to the World’s Leading Aviation Lawyers, September 2002, 27-28.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2006, July 2006, 61-66.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2008, September 2007, 76-81.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2009, August 2008, 79-84.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2010, September 2009, 88-93.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2011, October 2010, 92-97.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2012, September 2011, 99-104.
Ehlers P. Nikolai. Germany – Introduction to Getting the Deal Through, Air Transport 2013, September 2012, 105-110.
Ehlers P. Nikolai. Lake Constance Midair Collision: Bashkirian Airlines v. Federal Repulic of Germany, Air & Space Law, vol. XXXII, issue 1, February 2007.
Ehlers P. Nikolai. Montrealer Protokolle Nr. 3 und 4, Warschauer Haftungssystem und neuere Rechtsentwicklung (Montreal Protocols Nos. 3 and 4, Warsaw Liability System and Recent Legal Developments - 1985, Carl Heymanns Verlag, Cologne/Berlin/Bonn/Munich, Volume 7 of the series: Studies in Air and Space Law, editor: Prof. Dr. K.-H. Böckstiegel).
Ehlers P. Nikolai. Precision Pays, Air & Space Law, vol. XXXII, issue 6, November 2007.
Ehlers P. Nikolai. „Aircraft accident investigation and the determination of liability: a time for change?“; The Aviation Quarterly, Part 2, October 1996, 101-108.
Ehlers P. Nikolai. „Die Entscheidung des U.S. Supreme Court vom 18. April 1989 in Sachen Chan gegen Korean Air Lines zur Haftungsbegrenzung des Luftfrachtführers“ (case note on the decision of the U.S. Supreme Court of 18 April 1989 in re: Chan v. Korean Airlines); Zeitschrift für Luftund Weltraumrecht, 1990, 56-76.
Ehlers P. Nikolai. „Die Verfahrensregeln des Warschauer Abkommens: Artikel 26, 28, 29“; Transportrecht, 1996, 183-187.
Ehlers P. Nikolai. „Ein Erdrutsch in der deutschen Rechtssprechung zur Frage der Umrechnung des Poincaré Franc?“ (A landslide in Germany regarding the question of the conversion to the Poincaré Franc?) The decision of the Landgericht München I of 21 February 1984; Zeitschrift für Luftund Weltraumrecht, 1985, 68-73.
Ehlers P. Nikolai. „European Air Law Association: Sixth Annual Conference, Amsterdam, 4 November 1994“; Zeitschrift für Luft- und Weltraumrecht, 1995, 208-210.
Ehlers P. Nikolai. „European Legal Developments - Why European Law is Good for American Charter Carriers“; The Air and Space Lawyer (ABA Forum on Air and Space Law), vol. 10, no.3 (Winter 1996), 1, 6-12.
Ehlers P. Nikolai. „Forum non conveniens, U.S. courts and the dismissal of aviation cases“; Zeitschrift für Luftund Weltraumrecht, 1987, 329-350.
Ehlers P. Nikolai. „German High Court rules on conversion rate of Poincaré Franc under Warsaw Convention“; Haight's Memo, 1988, vol. VII, no. 1, 8.
Ehlers P. Nikolai. „New York Bar Exam“; JuS, 1988, 84-86.
Ehlers P. Nikolai. „Zulassungsvoraussetzungen zum New York Bar Exam verschärft“ (On recent changes regarding the requirements for admission to the New York Bar Exam); DAJV-Newsletter 2/1990, 30-31.
Hobe Stephan. Dinner address, in: P.D. Dagtoglou/P.N. Ehlers/C.O. Lenz/F. Montag (Hrsg.), European Air Law and Policy – Recent Developments, Sixteenth Annual conference, Berlin, 5 November 2004, EALA Papers Vol. 20, 2005, S. 207-215.