Pith Number

pith:MK77RJUT

pith:2020:MK77RJUTOIU2ECBZ7CHA27CO42

not attested not anchored not stored refs pending

Abrupt declines in tropospheric nitrogen dioxide over China after the outbreak of COVID-19

Aaron Page, Bo Zheng, Can Li, Fei Liu, Henk Eskes, Joanna Joiner, Lok N. Lamsal, Nickolay A. Krotkov, Oliver P. Hauser, Pepijn Veefkind, Pieternel Levelt, Ronald van der A, Sarah A. Strode, Sungyeon Choi, Yasuko Yoshida

arxiv:2004.06542 v1 · 2020-04-14 · physics.ao-ph · econ.GN · q-fin.EC

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{MK77RJUTOIU2ECBZ7CHA27CO42}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-07-05T00:54:52.997442Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

62bff8a6937229a20839f88e0d7c4ee6ad7da8d80904860fabe4455af5605768

Aliases

arxiv: 2004.06542 · arxiv_version: 2004.06542v1 · doi: 10.48550/arxiv.2004.06542 · pith_short_12: MK77RJUTOIU2 · pith_short_16: MK77RJUTOIU2ECBZ · pith_short_8: MK77RJUT

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/MK77RJUTOIU2ECBZ7CHA27CO42 \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 62bff8a6937229a20839f88e0d7c4ee6ad7da8d80904860fabe4455af5605768

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "3f73dddc6def860f2596b5a10ed753a2291524546ab51b50ec68e8e7c1bb996f",
    "cross_cats_sorted": [
      "econ.GN",
      "q-fin.EC"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "physics.ao-ph",
    "submitted_at": "2020-04-14T14:20:31Z",
    "title_canon_sha256": "a95972476e3f2e619dda6398d14aa8ff3e2510851a79a7f1297437f62eab736c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2004.06542",
    "kind": "arxiv",
    "version": 1
  }
}