Stettler, Lucia. “Geheime Gästekartei überlebt Hotelbrand – und birgt Zündstoff.” Schweizer Radio und Fernsehen (SRF), April 8, 2021, sec. Kultur. https://www.srf.ch/kultur/gesellschaft-religion/brisanter-fund-geheime-gaestekartei-ueberlebt-hotelbrand-und-birgt-zuendstoff.

<small><cite class='h-cite via'>ᔥ <span class='p-author h-card'>ManuelRodriguez331</span> in Advantages of Analog note taking : Zettelkasten (<time class='dt-published'>02/07/2023 08:33:25</time>)</cite></small>

At the Grandhotel Waldhaus in Vulpera, Switzerland concierges and receptionists maintained a business-focused zettelkasten of cards. In addition to the typical business function these cards served denoting names, addresses, and rooms, the staff also made annotations commenting on the guests and their proclivities.

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